I don't count the CH, because it would like be GI and replaced anyway, but yeah at good BCM BCG will set you back $190.
I'll donate a GI CH if it makes a difference.
My only issue with the Aero upper is the rail design. No idea why they don't do Mlok on all flats, when that useless two-hole design has to take longer (aka cost more) to manufacture.
I think this is the one I want, being that I don't know anything
PSA 7.5" PISTOL-LENGTH 300AAC BLACKOUT 1/7 NITRIDE 7" LIGHTWEIGHT M-LOK UPPER WITH BCG & CH - 5165449727
i wish I could remember what upper Silvers sent me for testing the 300blk back when it first rolled out. I put about 1k rounds of pre-production 300blk ammo through that upper, a lot of it through an AAC SDN6 when they first came out at a Pat Rogers class. Ammo even came in a white box, IIRC.
looks like it must have been a 9.5" given the 10.5" and 11.5" known barrel lengths in the first photo (and the trip down memory road looking for this photo has been entertaining! I had no idea it had been a decade since I did my testing with the 300 BLK but it was a 2010 EAG course where I ran this upper!)
eta: here's a fun one!
That is essentially the upper I use for 300BLK. Zero functional problems. I did run it with a suppressor and bent a parts kit bolt catch. I don't know if it was cheap parts or to high a bolt speed. After replacing the bolt catch and adding a heavier buffer I have had no further problems. Either way I don't hold the upper responsible.