i cant give you any personal advice on the sig mosquito but i've heard more negative than positive. irecently had to choose between the 2
i just purchased a P22 and put it through 1400+ rounds without cleaning. it was made this year according to the year code printed on it and i am very pleased with it.
out of those 1430 i had 7 FTF. 4 were CCI blazers . . . i only fired 30 CCI total
550 federal bulk from wamart had 1 FTF
500 american eagly by federal had 2 FTF
350 PMC Zappers no FTF VERY HOT ammo (made in mexico)
i keep the clips loaded with Zappers now.
Stripped and cleaned the gun with no problems, no unusual wear. very strong and fun gun. i read alot of bad reviews but it seems like they were all for the original P22's the newer ones are really great. i urge you to keep it an option.
since you already own a sig the mosquito would be a great training aide. i love sig, i with they made the mosquito . . . its definitely not a sig quality gun though.
consider the P22, good luck with the mosquito