Once I got my first muzzle brake I knew I was never going back.
Stoner designed the barrel to be in line with the stock to help reduce muzzle rise. However, when mounted properly, this in-line system is still above your shoulder. Thus, the toe of the stock being in your shoulder creates a pivot point and thereby causing muzzle rise.
Muzzle brakes are not all the same. Some are better than others. I have one of these on my .308Win RPR:
It works great.
I have one like this on my .223Rem AR:
It works pretty good too.
The more gas pressure there is, the better the brake works. The .223Rem generates about 55Kpsi at the chamber. This leaves enough gas pressure to operate the bolt carrier group and have enough left to give the brake enough to be effective.