Mine is a GR8 shooter, but the slide stop / release inaccessibility is a biggie. Here's an excerpt from another site I use, none are show stoppers but for the money I think they should have been a bit better thought out and executed.
The button release on the take down lever is scratchy, unlike my many other Beretta's I own or have owned which were like pressing a lubricated glass piston into a glass cylinder.
After the take down lever is forward, the slide stopped dead in its tracks halfway down the rails. I had to give it a forceful bump with my palm to get it off.
Note: Beretta says this is normal due to the tight tolerances of the X'Perf and only occurs on some pistols. They thought it would self correct itself over time and was not worth their reviewing the issue.
The slide serrations are vertical, unlike my other Berettas which have a slight forward rake. The vertical rake is uncomfortable for me.
The trigger is serrated... I have not had a trigger with serrations on it since I shot bullseye, and I do not like it. At some point I'll either replace the trigger, or grind this one smooth.
It has one major flaw... that being with the safety down, and the slide locked back, the only way to drop the slide is with the LEFT hand thumb. There may be some shooters with a snake like right hand thumb that can manage it, but IMO this wide safety on the left side is a total blunder and about the biggest blaring fault in the X'perf.
The safety also has an odd "feature" With the hammer down fully (or at half cock) the safety can be engaged. Why? As some sort of lawyer imposed safety? I always "thought" that DA mode was a sufficient level of safety. I'd rather have a mag presence safety like a S&W, then at least if someone were trying to get the gun out of my hands I could permanently rather than temporarily disable it. Better still, a (shudder) Taurus decocker built into the safety :-)
Quote off...
After shooting several boxes through it I find that the silly rail bites /scratches me when I rack the slide from underneath it. A rail on such a largish heavier handgun and hanging a doodad light or laser on it seems like putting a ginormous fat guy on a small donkey.
The X'Perf shot like a dream and it should, the weight of an all steel 9 makes that more likely than not. All the issues above are all nits but design committee's and marketers and attorneys are (IMO) designing guns nowadays so I can't expect different.