I do not own and have never held a CZ pistol, but I do own a Tanfo Xtreme and a Gold Team. Both guns have been shot many rounds and I have never had any issue related to the factory mags.
Some more info. The Alpha's footprint is slightly larger than the RTS. The Alpha's cover is soft plastic, the RTS's cover is hard plastic. The Alpha cover will fit the RTS but the RTS cover will not fit the Alpha.
Per Joe at PD the Defiant Limited Master has a target cone bull barrel like the stock 2 and limited custom guns. I ordered one today but will be end of January (probably) before I have the gun in hand.
Now comes the wait. Tick-tick-tick.
I have 2 Alphas and one RTS2. They both share the same footprint. The Alpha's on/off buttons are easier to use and seem more positive in using. Both dots are easy on batteries. Other than the buttons both dots are very similar in size and quality.
I recently purchased 4 new GEN 2 mags for a custom STI limited gun I purchased. Not one issue so far but I do not keep them loaded except at a steel challenge or outlaw match.
I have a gold team and xtreme in 9. I've tried the Lok grips but I prefer the Henning checked grips. See below link.
https://www.henningshop.com/Detail.aspx?PROD=1284113&CAT=9249
I have two on my Tanfos and really like this optic. I'm not a 1,000 round a week shooter but have put approx 1,000 - 2,000 rounds on each and so far so good. Dot is bright and well defined, optic stays zeroed, adjustments are easy if needed.