Congrats, the 539 was a one year gun only about 8000 were made. That makes it not so rare but uncommon . Good find and I am envious , I'm not a collector but I'm always on the look out for a 539 at a fair price. I just like all steel guns for shooting plus they have more soul than any ones plastic guns. Yes I do have Glocks, a Walther p99 an XD and a PX4, sorry M&P you were just a bit late to the poly game. Good luck with that sweet 539.