I had an older Para way back when they first came out. It was aluminum and I saw the slide-stop hole get elongated after only 1000rds. My philosophy since has been to carry your aluminum guns alot, and shoot them a little. I am but a novice, but having an aluminum gun I want to shoot is just a potential problem I dont want. Thats why my Colt Defender stays in the safe, and is shot only 2 or 3 times a year with 1 mag or maybe 2.