Things I liked:Great extra magazine. I have 3 that I just bought for my son for christmas. We have used them around the backyard to test them and they are great.Exact copy of the t77, 203zx, Ksc m11, kwa m11a1 1st gen, or hfc 203 m11 magazine that comes with the guns. Works great. Pyramyd air is great!!!! Things I would have changed:Mabye Make a larger ammo capacity like 60 rounds although it may be too long with that, and also maybe make a short magazine 25 rounds or so to use an m11 as a side arm. What others should know:Keep it well oiled with silicone in your propane but do not oil the exterior spring and loading button.