Im running 7psi from the T3 on standard internals. Done about 5000 miles now and running sweet. Please with how quick it is. 
When i first did the conversion i did a small (and im sure inaccurate video) and 0-60 was about 7.5 - 8.0secs and that was with lower boost than im running now, standard biscuit tyres, standard suspension and my MK1 bodged exhaust.
Now im running double the boost, coilovers, 15 x 7 steels and decent MK3 version exhaust.
Will get another video up at some point.