My buddy is looking for a 3x flip up magnifier for the exps2 on his scar. I only have experience with the eotech g33. Anyone have experience with the aimpoint, vortex or burris? I know the vortex flips left and if you reverse the mount the button is on the wrong side. I warned him and he said if he would use the vortex with a burris mount to rectify this. Any input?