Hi everyone,
I remember looking for threads just like this when I was shopping for an S5, so I thought it might be helpful to someone.
I've now owned both a 2010 B8 S5 Coupe with the V8 (tiptronic) and now a 2015 B8.5 S5 Sportback (DSG). This should hopefully remove a lot of bias from other comparisons made.
ENGINE:
First and foremost, the supercharged V6 is undoubtedly faster across the board. Not by a huge margin, but definitely noticeable. It will more often give you the sensation of putting you back in your seat, although it's not neck-snapping like turbo vehicles can be. In that regard, the supercharged V6 almost feels like an N/A - the throttle is always there and ready to go after a split-second lag, but it's certainly not quite as instant as the V8. I found that the V8 lacked that sense of acceleration in any gear but first, whereas the supercharged V6 can still give you that feeling even in third gear. I believe both engines are of a similar level of reliability, although both can be known to burn oil (both of mine did).
TRANSMISSION:
I never had a problem with the 6-speed ZF tiptronic in the V8. It shifted gears fairly quickly and is known to be reliable. The 7-speed DSG definitely shifts much, much faster on the upshifts, but felt the same on downshifts to me. However, the DSG is also known to have some reliability issues and I also find it uncomfortable to drive in stop-start conditions such as creeping forward in traffic - it's not quite as linear and predictable as the creep in the tiptronic. This is made worse by the auto stop/start function to save fuel - the DSG is very uncomfortable because it takes a split second to turn the car on then another split-second for it to engage the clutch, so it's too delayed - I have it off permanently because of this.
HANDLING:
The front end of the b8.5 V6 seems lighter, likely due to the different weight of the engine or its placement. This gives it a sharper turn-in and a slightly more agile feeling. That said, you can definitely notice the extra dimensions of the Sportback to a Coupe - it feels like a sedan (because it is) whereas the Coupe felt like a shorter, better handling vehicle to me (which it probably is - go figure). Then again, it's nice to have useable back seats (and this is ultimately why I moved from a V8 to the Sportback). I personally think both of these models have the notorious "numb" handling of a quattro Audi, and I generally find most BMW and Mercedes have better handling in almost all situations.
EXTERIOR/INTERIOR:
This is subjective, so I won't go into detail here. I actually like the older b8 styling when the DRLs are on - it has a more masculine and aggressive look versus the b8.5. The interior is mostly the same except for the steering wheel, which is a nice flat-bottom in the b8.5 and much nicer than the older b8. I believe other options were widely available across both models, so it depends on how your particular model is specced.
EVERYDAY DRIVING:
This is where the main difference occurs, and is also the main reason for me writing this post. Strangely, although the V6 supercharger is faster - it doesn't "feel" as good as the V8 and I'll try to explain why. First of all, the V8 sounds much, much better - you can't really beat the sound of a V8 in my opinion. The V6 has a muted, boring note from the factory. This immediately gives the car a different emotional feel. The V8 somehow feels more "premium" because of this. Additionally, the V6 generally feels a bit cold and clinical to drive - the smooth linear power delivery and the DSG makes it feel like playing a video game, whereas the V8 somehow feels slightly more visceral even though it's the slower vehicle. Because of this, I find that I'm less excited about driving the V6 supercharged model everyday. I also realized that most of your daily driving is slow - in traffic, in low-speed zones, etc (as it should be when obeying the law) - and the V8 just feels better to drive slowly, like a premium GT cruiser rather than some kind of sport sedan.
I don't think I'd go back to the V8, nor would I buy another V6 supercharger, just because my sights will next be set on an S7 or newer b9 turbo S4/5.
Of course, this review hasn't taken into account the tuneability of the V6. There's very little you can do to extract more power out of the V8 (short of expensive supercharger or turbo setups), whereas a stage 1+ tune in the V6 can get it into RS territory. I haven't yet experienced a tuned V6, so I can't comment on it.
I hope this helps someone out there. Of course, you can't beat test driving both models in person to get a better picture, but I only started to notice the "everyday driving" differences after actually owning the vehicle for some time.
I remember looking for threads just like this when I was shopping for an S5, so I thought it might be helpful to someone.
I've now owned both a 2010 B8 S5 Coupe with the V8 (tiptronic) and now a 2015 B8.5 S5 Sportback (DSG). This should hopefully remove a lot of bias from other comparisons made.
ENGINE:
First and foremost, the supercharged V6 is undoubtedly faster across the board. Not by a huge margin, but definitely noticeable. It will more often give you the sensation of putting you back in your seat, although it's not neck-snapping like turbo vehicles can be. In that regard, the supercharged V6 almost feels like an N/A - the throttle is always there and ready to go after a split-second lag, but it's certainly not quite as instant as the V8. I found that the V8 lacked that sense of acceleration in any gear but first, whereas the supercharged V6 can still give you that feeling even in third gear. I believe both engines are of a similar level of reliability, although both can be known to burn oil (both of mine did).
TRANSMISSION:
I never had a problem with the 6-speed ZF tiptronic in the V8. It shifted gears fairly quickly and is known to be reliable. The 7-speed DSG definitely shifts much, much faster on the upshifts, but felt the same on downshifts to me. However, the DSG is also known to have some reliability issues and I also find it uncomfortable to drive in stop-start conditions such as creeping forward in traffic - it's not quite as linear and predictable as the creep in the tiptronic. This is made worse by the auto stop/start function to save fuel - the DSG is very uncomfortable because it takes a split second to turn the car on then another split-second for it to engage the clutch, so it's too delayed - I have it off permanently because of this.
HANDLING:
The front end of the b8.5 V6 seems lighter, likely due to the different weight of the engine or its placement. This gives it a sharper turn-in and a slightly more agile feeling. That said, you can definitely notice the extra dimensions of the Sportback to a Coupe - it feels like a sedan (because it is) whereas the Coupe felt like a shorter, better handling vehicle to me (which it probably is - go figure). Then again, it's nice to have useable back seats (and this is ultimately why I moved from a V8 to the Sportback). I personally think both of these models have the notorious "numb" handling of a quattro Audi, and I generally find most BMW and Mercedes have better handling in almost all situations.
EXTERIOR/INTERIOR:
This is subjective, so I won't go into detail here. I actually like the older b8 styling when the DRLs are on - it has a more masculine and aggressive look versus the b8.5. The interior is mostly the same except for the steering wheel, which is a nice flat-bottom in the b8.5 and much nicer than the older b8. I believe other options were widely available across both models, so it depends on how your particular model is specced.
EVERYDAY DRIVING:
This is where the main difference occurs, and is also the main reason for me writing this post. Strangely, although the V6 supercharger is faster - it doesn't "feel" as good as the V8 and I'll try to explain why. First of all, the V8 sounds much, much better - you can't really beat the sound of a V8 in my opinion. The V6 has a muted, boring note from the factory. This immediately gives the car a different emotional feel. The V8 somehow feels more "premium" because of this. Additionally, the V6 generally feels a bit cold and clinical to drive - the smooth linear power delivery and the DSG makes it feel like playing a video game, whereas the V8 somehow feels slightly more visceral even though it's the slower vehicle. Because of this, I find that I'm less excited about driving the V6 supercharged model everyday. I also realized that most of your daily driving is slow - in traffic, in low-speed zones, etc (as it should be when obeying the law) - and the V8 just feels better to drive slowly, like a premium GT cruiser rather than some kind of sport sedan.
I don't think I'd go back to the V8, nor would I buy another V6 supercharger, just because my sights will next be set on an S7 or newer b9 turbo S4/5.
Of course, this review hasn't taken into account the tuneability of the V6. There's very little you can do to extract more power out of the V8 (short of expensive supercharger or turbo setups), whereas a stage 1+ tune in the V6 can get it into RS territory. I haven't yet experienced a tuned V6, so I can't comment on it.
I hope this helps someone out there. Of course, you can't beat test driving both models in person to get a better picture, but I only started to notice the "everyday driving" differences after actually owning the vehicle for some time.
