I don't know why people keep referring to the CZ 75 platform as "whipsterish". Nothing on the market touches its performance at the price you get one in 2023. It's history is legendary. A war pistol thru and thru.
The mec-gar standard mags *used to be* 14 and 16 round mags. What he did was take the SP-01 baseplate (doesnt add capacity), and put it on a 16 rd mec-gar. It fills the gap perfectly!! Newer mec-gar mags are 15 and 17 rds, and wouldn't look the same with the sp-01 baseplate, as far as i know