Things I liked:when it worked it was cool but that was seldom. Things I would have changed:I would make it so that the co2 cartridges would actually engage and not leak or not even pierce. I tried twice in getting this weapon and they both had trouble with this and they both had trouble feeding ammunition from the hopper to the magazine. I give it a thumbs down. Pyarmid air did nothing to address the problem other than to sending a new one What others should know:Don't buy it, it will frustrate you to death.