yes i do have the simtek fitted (first one on a newage )
rgards the turbo, it depends on if you want to buy new or 2nd hand, new vf35 can be found for around £300, there is one in the for sale section.
if you are getting new, then the vf34 is a good buy, very similar to the vf35 but with roller bearings. Think www.enginetuner.co.uk sell them for about £650ish (dont quote me on this).