The reset on the PPQ was super short. That combined with a light trigger had me accidentally doubling a few times when shooting with any speed. If it were going to be my one-and-only pistol, I would've kept it and just gotten used to it. It didn't seem like a good idea for me to have that in the mix with my Glock 34 and P30 LEM.
The VP9 is somewhere in the middle between the Glock and Walther. I like it, but am not sure I can come up with a good reason to buy one unless I came across a deal too good to pass up.