Seriously, I don't think you will be upset with the purchase. Out of the box, it is fun. Really fun, but when you have put a few mods on it, you will get everything you can out of it (mcarbo spring and metal pin kit; trigger spring reinforcement) you can. I don't think this will need to be replaced for a lifetime.
I can't figure out what else NEEDS (aside from the clip) to be added/modified, so until my next weapon, this is my final build.