I did the solventtrapcups.com one for my 308 ar. When I was at the range and shot it there was like 6 guys from down at the other end of the range come over and say hay what caliber is that, I said 308, they said man that thing is quiet. Plus you can buy the internal parts seperate in case you mess any of them up.
Tarey
Sign up on their mailing list and they usually have 20% off.