I mainly got because I have PT Evo grips and the mag can get stuck during a reload. The magwell funnel is convex and has a smaller hole so the magazine can only go straight in preventing it from getting stuck.
I am in the same boat. My RO is also at 42.6 with the same part except a tungsten gr and magpul grips with silicon carbide. I had the slide tri-topped also. I would like to get an ambi but the only ones I have to weigh are PT's w/thumb shield on my open guns and they are def heavy.
I agree with sporky. I started with no holes and went to 3x 1/8" holes. Slight difference. So I went to 3x 3/16". Better. I wouldn't go back to no holes.
The manuf tumbles them. I find corn media in my Montana Gold JHP all the time. I wet tumble and have no corn media here. I always check when boxing. It can ruin your match.
I shoot USPSA, steel challenge, bianchi, pro-am and steel matches all with 2 identical 9 major guns. I don't change anything as my main focus is USPSA. All the other matches are practice.