The best thing is to have the barrel rethreaded. They're not cheap rifles and you're making a very weak link if trying to add a suppressor or muzzle brake.
When my TRG arrives, I'm going to have a muzzle brake rethreaded rather than the barrel. I'd rather leave the rifle alone. I realize that it doesn't give quick change options, but I'm OK with that.
Yyyyyeeeessssss what sean said^^^^^^^^^^^^^^^^^^^^^ cheaper to thread that a baffle strike or messing with hundreds of loads to find the right one if at all possible.