The kit you are looking at looks like a Chinese knockoff kit. The turbo isn't going to last long. Hot Rod magazine had a big article a couple months ago dealing with these Chinese turbos. I think they bolted one up to a 3rd gen Camaro or something like that. It made power. However, there was tons of fab work and who knows how long the turbo will last. I vote not too long.
Search Google for these knockoff turbos and you'll find some crazy pics (like compressor blades breaking off).
The piping isn't going to directly bolt on to your '11 Focus. You would have to custom cut the pipe. If you have the money to buy the kit you are looking at I would HIGHLY recommend saving that money toward a legit kit (FSWerks, Top Speed, etc). These kits are expensive, but there is a reason for that.
FR '11 FF Moderators pick
Oct '11 ROTM
FR '12 Carlisle Nifty Fifty Award/Best in Boost/Best 08-11/Finest Five Pick