Ive had both. I had a II 42% by its self and it ran great. Now i have a stock one with the modded one and the throttle response is way better and it does feel faster.
As good as your tuning will allow. And use the wastgate to limit boost and you should be plenty good. FWIW on my stock tune my truck only made 440hp so if you keep tuning modest you can be well in the safe zone.