I just ordered PML's 3" Bull Pup kit. I'm looking forward to the build. I had one before and ended up selling it on here, the reason I should of used a cleaner looking retainer, like the Slimlines that GLR sells. Also instead of going with the nylon shock cord with the kit, I'll pick up a pre-sewn nylon cord from Topflight and use quick links as attachment points. I'm still going to go with the piston ejection system. I think its a cool concept. I'll lay down a really smooth paint job and get some custom decals made from Stickershock. It seems once you build a kit once you learn so the next time it turns out much better!