Mention Sig .22 pistols and most people immediately think of the Mosquito. The Mosquito gets a lot of bad press but I have one that's reliable and accurate so they are OK. What some folks don't know is that Sig makes factory .22 versions of their popular P series guns.
There are available in the 220, 226, and 229 series and go for about $400-$450 or so. Included with the gun is a coupon from Sig which lets you purchase the centerfire conversion for your .22 for $399 and the coupon is good for a year. As I wanted a real "duty" style .22, I selected the P220R in single action only trigger. I found this one on special at Buds a few months back for $399 delivered so it was a good deal as well.
I picked it up and took it home and gave it the thorough cleaning a new gun requires and the next day it went to the range. I brought along 3 types of .22 ammo to give it a good test. I had CCI Mini-Mags, Winchester 333 bulk, and Federal bulk (both bulks from Walmart). My goal was to put a lot of rounds through it quickly to gauge the reliability.
I started the test with 100 rounds of CCI and I had exactly zero problems. The gun was every bit as accurate as I expect a Sig to be. Next I went to the Winchester bulk and put another 100 rounds downrange with the same results. Finally I switched to the Federal and on about the 4th mag I had a single FTE and the round "felt" under powered when I fired it.
In one sitting I put 300 rounds through the gun with a total of 1 FTE - pretty impressive to me. The real benefit of these Sigs is it allows a handgun newcomer to begin with a .22 and then swith to centerfire while not changing the platform at all. I highly recommend them.
And yes, I have other "dedicated" .22s, 2 Rugers (Mk II & Mk III both stainless) and a S&W 617 (along with the Mosquito mentioned earlier)...