All good info from BCEagleAce. OC/mace is cheap, so buy a gun at the same time if you can afford it.
The only thing I disagree about is the choice of the Mosquito. Do not buy a Mosquito without AT LEAST seeing how the trigger feels. I've heard good things from some people, and bad things from some people, but my experience with a friends sticks the most...
With a brand new Sig Mosquito, Sig mags, CCI HV ammo, and the proper recoil spring, the gun had AT LEAST one failure per three rounds for the first 200-ish rounds. The trigger pull (MA trigger) was insanely "gritty", stupidly heavy, and had such a hit-or-miss release point that we'd regularly either pop off a round early in the pull or have to actually release and re-grip the gun to get enough travel to fire. I'm not positive how many rounds he'd shot through it before he sold it at about a $150 loss, but I'm fairly sure it was around 1000 rounds.
It was a shame, since the finish was great and it fit my hand perfectly. It was and still is absolutely the #1 most disappointing gun I've EVER shot.
I personally prefer the Ruger .22 autoloaders (even with the finnicky disassembly/assembly of the MKIIIs). While I have not shot one myself, I was fairly impressed with the Walther P22 since it nicely fit my girlfriend's smaller hands and allowed her to hit the slide lock easily while not feeling overly small in my hands.
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