pro: feels like real. really good power and blowback feeling. can shoot about 3 mags for each co2 cartridge. If you want a affordable way to pratice glock shooting, this is it!!! con: hard to change the co2 cartridge. the trick is: don't screw all the way in. once the o-ring is buried by the thread, prepare to stop screwing. also, when taking out the co2, first unscrew the small screw to release residue gas. then unscrew the big screw.