I believe there have been 3 generations (changes to follower design) of the OE SIG magazines.
Your description of two extended magazines suggest they’re 3rd generation, and supposedly the most reliable.
That said I have an early P238 and haven’t experienced any issues with any generation of the SIG magazines, nor the colt mustang magazines that I've tried. I would check each magazine for reliability before replacing them.
If you need extra magazines SIG was running a special a short while back. I believe they were 3 (extended version) for $108 shipped. If interested check with and order through customer service. If not, they appear to run the sale periodically.
Good luck!