I've owned several .22 pistols over the years to include one of each of the models asked about. I've quickly gotten rid of the S&W and Beretta and 4+ yrs later still own and frequently use the P-22. I wouldn't trade it for anything.
Over the years since I purchased my P-22, I've read many articles about different owners having issues on FTF and maintenance issues but have yet to encounter any problems personally. I've fired as many as 700+ rds without cleaning with no issues, and I never purchase expensive ammo as some insist is needed (all I target shoot with is CCI).
I'm not saying that the S&W and Beretta aren't good pistols, I just personally didn't care for the comfort of the models when it came to carry or use. The P-22 has been spot on for my recreational shooting needs. I even recently purchased a second one (a pink digital camo model) for my wife.
Murph