I was one of the original beta testers with the AMP11. Worked purty dang good, but as others have said, it’s a brick. The added weight made it deadly accurate and recoil almost nil, but I can never leave a good thing alone. I reduced the weight by half. It now looks highly customized and is a hell of a lot lighter. I did an aluminum mag block for it using MP5 mags which I was immediately strangled out of. It allowed the use of the 30, 40 and 100 round Beta C drums for Mp-5s. It was well funneled and utilized a thumb mag release more like an AK than an HK, but that fixed the major stumbling block that the gun had...ie, you HAD to have all the mags perfectly aligned or they wouldn’t go in. There was no wiggle room like Lage uppers had. Having both the Lage upper and an AA upper, the Lage upper was definitely better for competition. My MP5 mag block made it equal.