It's a POS. Even by ACM standards, it's QC standards are horrible. Internally, it's like you just got whatever they had laying around. Some people got a metal hopup, some got a clear plastic one. Some got a metal sector chip, some got a plastic one. Most people's stock's don't lock in the folding position. The spring is completely random. The motor sucks. Accuracy sucks. Mine requires a rather firm whack to ensure the mag is locked in regardless of mag used.
Even people who have gotten a "good" one, still replaced half the internal parts.