All in all, the Walther P22 gets my vote for the best all round small pistol. But I might be a little biased…Of all the afore mentioned, I think the Walther P22 is the only one that will come close to being a micro. Also a very sweet shooter. My wife and daughter both like shooting those and the PPK/s 22. Other viable options might include a little Taurus PT with the tip up barrel, which is a Beretta clone but has a pretty stout double action trigger, or even one of the elcheapo offerings from Jennings, Phoenix, Jimanez, etc.
The Taurus TX is extremely lightweight but closer to a full size pistol, the Ruger SR is a little smaller but robust and heavy. The Ruger LCP2, however, is another sweet shooting little pocket gun.
I had a mosquito years ago that I wouldn’t keep as a tackle box gun. Sorry to know Sig is still struggling with the .22’s. I wonder if they contracted the 322 out too.Another vote for the Taurus TX22. That's one of the best plinkers on the market, and that's before you find out it only costs 250 bucks.
Limited reports on the Sig P322, but the only person I know who has one (@sportsbud) says it's an unreliable piece of crap.