I've had both a stage 3 T3 conversion and a T34 one

T3 one boost up a lot quicker and the repsonce is very quick.. Downside is it runs out of puff when your giving it some bananas

T34 is more laggy but more power up the revs..

Both nice conversions.. Running a T3 @ 1.3Bar (20psi) would make a wicked little driver