I have several different brakes that I have tried on my 300 win mag.
The OPS brake is a good one in that it doesn't kick up a bunch of dust when you shoot prone. The recoil reduction is pretty good. You won't see the hits on the deer size game unless you have a scope that is less than 15 power or so.
I have a defensive edge brake that works really well also. Seems to be comparable to the OPS brake.
I have a Gentry brake that really didn't seem to work very well. I had them leave the bottom blank so I wouldn't be kicking up dust. It is neither quiet or effective.
I have shrewd brake that is horribly loud. Ear muffs and plugs are required and then you ears still ring after a few shots.
Bottom line is the OPS, inc. and Defensive edge are the best that I have tried. I will be trying out the one Kirby makes to see if that is better. I too want to see the impact.
Good luck with your choice.