Here's what you do......don't give it a second thought, lol....if one arm were 17" and the other 15", you'd have a problem. 1/4" is subtle and could be due to a lot.....Like Sarge said, if you don't look like a weirdo walking around and people don't point and stare, don't sweat it.......And, don't reply with the "But I am a BB, every little detail matters"....even if you're a bodybuilder, look at pics from the last Olympia, those guys are a symmetrical disaster, lol.