Got one of these with my WE silver m1911, I got lucky and got a good one, and (at least I think) it's gas efficient, after shooting off 15 rounds on a 20 second charge of propane, I brought the gun inside since it was cold out. When I pulled the trigger 20 minutes later inside the house, there was to my surprise still enough for 10 to 15 more shots.
black(goes nice with the silver)
Spring doesn't get stuck and pokes out through the hole where you load the bb's
should of got more.
Don't know if all mags are as good as the one I got.
Rating: [5 of 5 Stars!]