It always pays to ask the question when the forum has such a great membership of addicts.
Thanks.
One last response for pew pew: on my CZ mags, all the coating is worn off from the slot to the top of the mag's where the button rubs on the insert and the drop. My much "older" Mec-Gars have a very very slight mark or two above the button hole. They have many more inserts and drops in two CZ 75s than the CZ mags.
The radius on the top front of the CZmags are visibly bigger so the button can't bypass this section of the CZ mag. The MecGars mag nose bypasses the release up top. No finish scraped to bare metal streaks in this area.