Just one thought turbo developement do a hybird turbo too, might be wirth calling them.
There is a guy with a Golf van running a hybird, he had an allarad v2, then changed to a stage 2 Turbo Developments turbo.
He said the Turbo Developements turbo was way better, ie less noise, less smoke and similar power....
I believe its the hybrid most tunners use? AMD, Star and Jabba to name a few.