Just gonna throw a wilcard in this, have owned both, and also recently a Modify PP2000.
I preferred the PP2000. The ergonomics are fantastic, it shot better than the mp9 at long ranges and almost as well as the MP7 if not on par, it was snappier in CQB too.
Within site limits out of the box, a decent hop unit, well made mags.
Comes in its own hardcase which is a touch.
The downsides are the long mags are freakishly long, and the barrel isn't threaded as standard (but a 14mm ccw die fixes this)
Also they are quite easy to knock into full auto but just something to be aware of.