Surefires I have used are very durable and forgiving but like you said they aren't quiet. Even the longer versions are loud
I have a Silencerco Omega and it's a great, light can. I would have chosen a can with more flexibility had one been in stock when I ordered mine. One thing I didn't like about 300BO is how loud the AR platform is. I had a 300BO pistol and the bolt moving around by your head was loud enough to not make it so "cool" for me. My 5.56 and (308 bolt with subs) sound awesome though. Good luck on your quest. Cans are a lot of fun!
A JP Silent Captured buffer spring and an adjustable gas block will work wonders in the quiet department.