Yeah, I'm not a fan of the modified Pierce Springfield XD mag extension. The problem is, you have to file off the top of the plastic extension in order to get the so-modded magazine to seat in the mag well, which weakens the slots on the extension that slide onto the bottom of the mag. This can cause the extension to pop off abruptly, dumping the contents of your magazine onto the ground -- not a good thing to happen, especially in a SHTF situation.
If you want to put a better, more comfortable floor plate / extension on your factory Rami 10-rd. short mag, I would suggest getting an extended aluminum base pad from CZ Custom. They are made specifically to flush fit on competition CZ75s, thus will fit Rami mags without need for modification. Aluminum > plastic.
https://czcustom.com/cz-75-flush-fitting-aluminium-base-pad-silver.html https://czcustom.com/cz-75-flush-fitting-aluminium-base-pad-black.htmlCZ Custom also sells longer or shorter extended aluminum base pads, as may be desired. Some increase magazine capacity, others do not, you'll have to check to comply with asinine CA law.