I just picked one up on Friday. I am very impressed. The PX4 9mm shot like a champ, the weight is just a little above what my glock 23, and the size is slightly larger than the glock 23 but is not full size either. I took it to the range on Saturday and put 200 rounds thru it. The PX4 grip was just about right for me. The magazines dropped free easily, but needed to be firmly inserted to latch properly. The slide release was easy to operate and the decocker safety was easily engaged or disengaged.
The PX4 shot flawlessly and smooth. The slide racks smooth and easily, when firing the slide operates with fluid smoothness and ease. The recoil is very much reminesiant of the couger, lighter than a normal 9mm, follow up shots are easily managed with the gun. A mediocre shooter like me can shoot the PX4 and look like a good shooter without even trying. In my opinion the PX4 is a far superior pistol than a glock.
The only immediate downfall right now to this pistol is that the front end is larger than a 92fs and a glock 23, this will make finding a holster to conceal carry the pistol difficult.
This review is based upon my opinion and experiences with different pistols.
I have owned a sig 228, glock 19c, glock 23, beretta 92fs, 96fs, cougar 8000f. In my opinion my berettas have always shot more accurate and pleasant than the glocks.