Honestly I haven't done a direct can on/can off poi comparison with supersonic loads and this particular can on either rifle. What I can tell you is I made no sight adjustments on the M1A with the can and it seems to be shooting right where my notes say it should last time I shot it with this ammo. With subsonics in either system, bullet drop is 5" at 75 yards from the bench, straight down with no windage shift. Believe it or not, accuracy with the subsonic loads is BETTER with the suppressor, go figure?
My choice of 'sided' when shooting boils down to being left eye dominant. I'm naturally left handed but like most southpaws do many things right handed due to living in a right handed world. From the bench I much prefer RH rifles because I can see the "works" without having to roll the rifle over in the bags or climb over the stock. I built the Hog Hunter as a LH because I wanted a bolt-action woods rifle, and while I generally find most RH actions to be no particular bother to operate LH, a bolt-action rifle is one thing that is tough to work from the shoulder in the field while keeping an eye in the glass. This is one reason I like leverguns so much for hunting, they work just as well from either shoulder.