In summary: a greased up super slick thicc girl - CMMG DISSENT 9mm, 10.5in Upper Receiver

The action on this upper is super slick, it is in fact the slickest semi-auto action I've ever felt and owned. It is near effortless to charge, there is no grittiness or stutters, its just smooth and slick. The upper is heavy though, this is probably due to the handguard and heavy barrel contour, this 10.5" upper on a mil spec lower weighs a whole pound more than my 16" Stribog SP9A3, furthermore the majority of the weight is in the front so its very reminiscent of a piston upper. They should absolutely offer a lighter contour barrel and I don't know why they went with 10.5", they should've offered it as a 8.5" barrel like the previous Banshee line. 10.5" is a little too long and 6.5" is okay but the handguard is too short, 8" would've been perfect. I do have a non-functioning 8" Banshee and I've thought about swapping out the barrels because apparently they are the same exact barrels but then I would have to find a new handguard that isn't available. I had to slightly sand down the top of the picatinny adapter since it was such a tight fit that the rear receiver pin wouldn't line up but this does make for a tight fit between the receivers with no wobble whatsoever. A ejection port cover would've been nice too.

One important spec that isn't available anywhere is that the picatinny section is raised .275" compared to a mil spec AR upper, so throwing a 1.57" red dot mount on this upper actually makes it sit at 1.84", this assumes that you mount your stock/brace inline with the barrel which is the middle picatinny slot on the adapter. If you move your stock/brace up one picatinny slot on the adapter, then it will be roughly 1.45" since the distance between picatinny slots is .394" (1.57+.275-.394=1.45)