the mag is for 5 rounds, realistic distance is 600-800 meters, that's lame. It's apparently very quiet, comparable to 9mm suppressed rifles (39x9)
If you are shooting at 1k-2k, like most 50cal are used for, I don't think that you need to be that crazy quiet. There are a bunch of flash hiders that reduce flash and dust kicked up by the rifle. Yes, you'll hear it, but figuring out where the shot came from, 1k-2k away isn't easy, that's a lot of horizon to scan, unless there is a cloud of dust rising.