I have a Sig Mosquito and like it. Except for the DA trigger pull, which is quite long and heavy. The pistol is near full size, controls are logically situated and easy to operate. Mine did fail to chamber often until I polished the feed ramp. (Seen that on some center fire pistols) It also comes with three different front sights to adjust point of impact, and a second recoil spring which can be substituted for ammo variations. (high vs standard velocity) It only comes with one mag, which sucks. New ones are $25 to $35 and getting easier to find. It is fun to shoot and fairly accurate. Also has a rail for lights/lasers, ect. All in all, with a little tuning, a fine training weapon, which is why I bought mine.
PS-Recently found a paper in the case behind the foam that detailed a lubrication point that evidently was missed in the manual.