Gramps - welcome (another gramps here!) -
Indeed, the pup has experienced some teething problems here and there but not I'd say more than any thorobred in its earlier days. Add to that superlative customer service from Bros R if there are prob's.
Being a close tolerance item it is a tad ''fussy'' - which means for most of us ensuring we use the ammo best suited to our gun. The recoil spring replacement every 500 rounds is in part a precautionary move - a means to ensure and maintain good function. I have not pushed mine to any limit but would imagine that figure could usually be doubled without necessarily having trouble... I prefer to stick to recommended measures.
Another thing, and I certainly do not say this as other than a reinforcement of Karl's words - this gun is not designed as a range plaything - not a plinker for huge ammo volumes. It is as Karl says - ''carry a lot, shoot a little''. It's prime purpose is defensive as against recreational.
I have settled as others have, like Duane - to shooting thru a coupla mags every month or so, using carry ammo and so then reloading with fresh.