sorry to hear it mate
like you say white smoke is usally water in the engine, does sound like your blower has had it so get that sorted and take it from there.
Turbos have shot up in price, you would at least expect them to last as long as the warranty, just to let you know i bought a turbo technics stg 3 unit for mine 7k ago. Never caused any probs at all, but then the company has been going a long time with a great reputation.
Do you allways allow the engine to fully warm up before you pick up boost?

like alvyn says, put your foot down with them