I didn't know that, no, but I should have. I have a GG&G flip sight on the faux gas block. The MBUS front sight would have been cheaper. It is a CMMG dedicated upper, 22 LR, blowback operated.
A really fun little gun.
I have a JP, single stage trigger on the lower. When I first shot it my eye got distracted by the stream of .22 shells flying out the ejection port.
I hadn't sighted in the scope so I wasn't hitting my target. Very easy to sight in. I got that lynx about a half hour later with it.