The Cessna 400 was until recently the Comumbia 400 and I think you'll probably get more info about this bird on the US part of Pprune or on any US GA forum (Avweb, etc). I don't think there are loads of them around Europe.
If pressurization is something you'd like to have, then you could also be looking at a C210P. While nowhere near as fast as a Mooney or Cessna 400 (and of course second hand) these are very capable machines.