The thing about poly is that it's so hard that it doesn't really wear in. It will chip but it won't wear. The practical effect is that a poly finish becomes a record of your klutzy moments but not much else. There will be a crater from that time you knocked your bass off the stand, and from when you swung the headstock into into the ride cymbal that time -- but unlike nitro it won't have the nice forearm wear spot from your hours and hours of yoeman work onstage or in the studio or whatever.