There's a difference in replacing an upper for performance purposes vs replacing it just because there's a blemish. A stripped AR upper receiver is a stripped AR upper receiver all made to the same specs. The benefits are in what bolt carrier group, barrel, and maybe charging handle is used. The same is true for Glock slides, and I been on GlockTalk for about a decade, and they frown on replacing factory parts with aftermarket parts. There was also a similar thread were someone wanted a new slide for their Glock 17, and the consensus was the same as mine.... It's just a tool. If I go on ARFCOM, AKFiles.com, or
M4Carbine.net and state they you want to ditch a perfectly good upper because of a cosmetic blemish, they're going to troll you.
Look up "distressed slides" and pictures of handguns that people actually own, carry, and use on a regular basis. They all show finish wear. It's inevitable and will happen to every firearm that isn't a safe queen or owned by casual gun owners who will barely ever use their tools.
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