Just for the record, I've shot a couple thousand rounds of 7.62x25 through my CZ52 and Zastava M57 and I've NEVER had even one misfire or dud of any kind... That includes new-production Sellior & Bellot ordered online and delivered to my door which is available through many companies... just google for a bunch. So, to me, neither reliability or availability is a problem whatsoever.
I would want to be able to use it defensively if the need ever arose.
Well, jeepers creepers, thousands of commie-bloc uniformed personnel carried 7.62x25 weapons during many decades. They weren't idiots. Anyone who's shot one KNOWS they wouldn't want to be shot BY one.
PS: As mentioned above, the CZ82 in 9x18 is a great alternative and was a next step in the evolutionary design process.