I've had it for a month, & so far its been great.Only upgrades to it have been a (455mm) length inner barrel, CA One Touch Replica Silencer, and a Magpul BAD Lever. I use to think I was goin to hate the blow back but I like it.to adjust the hop up.... the bolt has to be locked back which is way better than the older classic army m4's I own. Now I bought the BAD lever thinking it would work on my AR, but that didn't work, so I put it on the m6a2. well worth the $454 that I paid for it. As far...