Christian has an awsome turbo!
recently jamie p was selling alot of his kit and his is a top set up, might be worth chatting to him and maybe getting some of his parts, infact, lots of turbos have been up for sale. Do what Stonkin did and pop on to some of the sale threads and compare what people say in the write ups.
there are also the traders, these guys know there stuff and will listen to what you want from the car and tell you what would be best for you. i have no idea about the details on my single, i know its a t71 and its big, its laggy...ish but really goes at 3 half k revs. bought a smaller one which i then sold to stonkin and he says its great, which was a smaller (less lag) presision t62.