If your wife liked the P22 best then get her one. You can always get more guns later but humoring her now and getting her what she likes will be a big step in making her gun friendly for life.
Re: Opinions needed: glock gen4 21SF vs S&W 'M&P in 45
I carried a Gen 3 21SF as a duty gun and it was 100%. No problems ever, just like everyone else.
Re: Value revolver similar to Ruger SP101?
Look for a used SP101 if you want to save money. They are bullet proof and if theres any problems Ruger will take care of you.
Re: Sig P239
I don't know if its actually stainless or not but the "diamond plate" sigs actually have a diamond plate pattern and look like ass. I'd just get the plain black one, it will look a lot classier and be easier to sell later if you want.