So, so far I've installed the 034MotorSport billet aluminum transmission insert and the transmission mount, as well as JHM's solid shifter linkage kit. I'll give a quick review of the products so far.
The 034MotorSport billet aluminum insert and transmission mounts are a MUST have for the B8 platform. The new mount is made of rubber that is approximately double the stiffness of a stock/brand new transmission mount. After installing these two products I don't feel as if my car is "thinking" about accelerating, or slowing down in response to my throttle inputs. The car just does it. The spot-on good shifts are so rewarding now. Judging by the good ol' "butt-dyno," I wouldn't say it's really any faster. It just feels better over all. It feels smoother, too. Contrary to what one would think. I'm still in the break in period for the transmission mount, which is about 200 miles. I would say the only perceived added NVH to the cabin is some incredibly subtle transmission whine. (I had to keep my ear basically as close to the center console as possible while still seeing the road, with the music off, to hear it.) As well as perhaps some slight added vibration at under 1,500 RPM. Other than that, for the price, it's really, really worth it. Installation was very easy, and took about half an hour.
Regarding the JHM Solid Shifter linkage, this is probably so far aside from my exhaust my favorite upgrade to the car. There's no more hunting for gears, or occasionally wondering what gear you're in. There's no more slop. It's smooth. It's tactile, and gives great feed back. It's not got some of the greatest shift feeling I've ever felt in a car, and I haven't even done my short throw shifter yet. The stock shifter linkage had an unbelievable amount of play comparatively. Installation was relatively straight forward, and took maybe an hour and a half or so. Fighting with old bolts and what not. Trying to reach over the transmission for the stabilizer arm was the worst part of it physically. Before adding this upgrade, I sometimes wondered if I should have just gotten an automatic/S-Tronic transmission. But after getting this, I am VERY happy that I got a manual and did upgrades to it. It's expensive, but, if you have a manual it doesn't get much more satisfying than this. It's a part you feel and operate with your hands every time you drive your car. This is a necessary upgrade.
This weekend I'll likely be adding in the sway bar, and probably will do my short throw as well. I'm keeping my eyes on the watch for some coil-overs too. More to come.