Well there's good news and bad news in regards to the quad tips.
The good news is that they are a great looking exhaust that will not disappear as they become less shiny over time. The outer rim of the tips is beefy enough to be visible regardless of sheen.
The tips are very large and will not suit everybody. I think they look great, but they are 3.5" openings which is quite a bit larger than your standard 3" opening. They are also very low luster that have a more machined look to them than the standard stainless tips.
The bad news is availability is a couple of months out (early January), and they will only be doing a limited production run due to the difficulty in the manufacturing process because of the design.
The limited availability I guess can be a good thing if you're lucky enough to get one of the estimated 25 that will be produced. I have dibs on one so they're down to 24.
I did not hear the exhaust personally, but Fabryce stated that the sound is the same as the dual ovals. The exhaust is setup with dual cans with intricate piping inside the muffler. Imagine an x-pipe leading into the exhaust tips. That's what it looks like when peering inside the tips.
Here are my iPhone pics, but I know Suprablur got some nicer ones that he will be posting soon....