I was looking to save some money by shooting 22LR. So, I bought a Mosquito and it works -- now. It is an early example.
It always worked with CCI high velocity ammo. But it would jam or fail to fire or fail to eject with regularity with anything else. It gave you a lot of clearing of malfunction drills. I was to say the least disappointed in it. The Mosquito is to be blunt up to the usual Sig standards.
I complained on this forum about it and included a note here to Micheal Bane to get Sig to find a fix for the darn thing.
I went to the NRA Convention and talked to the folks at Sig about my problems with the gun. One of the Sig instructors I talked to told me to try putting a drop of oil in the little hole on the side of the slide. When I got home I tried the suggestion. It worked. Now I still shoot it, but I don't have the stoppages at the rate I once did. Now it works with bulk ammo from Federal, Remington, and Winchester not just CCI. I am shooting some of my old backlog of Mohawk, Imperial, Wildcat, and other cheap junk I bought years ago, many years ago and it works. It even works with standard velocity ammo. I do not claim I do not have stoppages, but they are few.
I think mine works because it got shot a lot and I keep it well lubed. I also keep the crud out of the breach area by keeping it as clean as I can with the M16 toothbrush. I do not do a major cleaning every time I shoot it because I have a Sig red dot sight on it that makes a major cleaning a bigger pain than I am willing to put up with.
I have kept it because it is a surrogate for my 226. But now Sig has 22LR conversions for the 226. They had several examples of the Mosquito at the NRA Convention in Pittsburgh. So maybe they have solved the problems.
As for the future I am going to get one of the new 1911 style .22s.