Mine is the PX4 sub-compact, works a bit different. Liked how easily it actually conceals, liked the design / operation better, the quality, etc. And the fact that several agencies had been carrying them for 3-4 yrs before they released them to the public. During that time, they also fixed, resdesigned, changed , etc. any issues brought up by the Depts using them. The response of Officers were very positive. So, that was a selling point to me and I talked to some who had been carrying them. The PX4 is considered part of the "Storm" series.
For a couple of years at least, there were some issues with Storm Compact in the .40 cal, and more in the .45 cal versions. But, it seems they got all of those worked out and fixed and haven't heard of anything new. The 9mm's never seemed to have those issues, or that I ever heard about. I know a few officers that carry them as their personal guns ... and they all like them.