If you mean Ultimate Velocity, don't go near them. I was considering one from them, called to ask if they had any in and was told they did. I drove down on the Saturday morning (from Leeds) and when I got there they decided they wanted £100 more than advertised on their website, and would need a 2 week lead time to order one in. I thought that was bad enough, but then they decided to check with their "expert" fitter which version I would need. He replied with "What car? A new S3? Yeah, that's an MFD2" (That's the unit in the MkV Golf and new Passat) It was at this point that I left.
I can't remember where, but since then I've heard a couple of stories about the fitting that they've done too. Let's just say that it leaves a bit to be desired...