I know one generally replaces the recoil spring on a 1911 full size at about 3K rounds, 2K rounds on a Commander, and Kimber is saying, replace the recoil spring on their Officer size .45 at 900 rounds! So, I wondered, "How often should I replace the recoil spring assembly on my XD .45ACP Compact?" I didn't see the answer here, so I e-mailed SA. I will not cut and paste the e-mail, as there is a disclaimer, requesting that it not be forwarded, etc. But here is what the customer service rep said. 'XDs have been tested to 25K rounds and beyond without parts replacement. Depends on what ammo you are shooting. Change it sooner if shooting +P, later if shooting reduced or target loads. Maybe replace the recoil spring assembly around 10K rounds, or if you notice that the fired cases are ejecting much farther away from the gun than when it was new. The Part Number is XD4591 and the current retail price is $29.'