If you are asking about the Sig Mosquito, Then no they do not stock it, They have had so much trouble with them that they will order it for you but that is it.
I have never had a problem with my p22 but I cant compare it to the Sig because I have never owned or shot the Sig. All I can say is that the p22 has been great to me.
The P22 and skeeter have become so popular because they are one of the quickest guns to set up for a suppressor. The P22 is also quite popular with the ladies as a training firearm. I own quite a few Rugers and Buckmarks but have never had the desire to own either the P22 or the Sig.
If you are asking about the Sig Mosquito, Then no they do not stock it, They have had so much trouble with them that they will order it for you but that is it.
i think the problems with the mosquito jamming were from earlier runs of it. i picked one up in january, and put around 500 rounds through mine so far. as long as you use cci mini mags like sig suggests, and use the correct recoil spring, the gun fires flawlessly. i made the mistake on my first trip to the range using the incorrect spring with the mini mags, and i was having multiple issues with FTE. after switching the spring (which comes with it) i've only had firing issues with federal bulk, which i will no longer run through it.