Most of my cylinders are 1/2" tapered. No problems with any dive shops around here, other than a pained look by one guy who would rather not have had to hassle with them, but he did. Some hydro guys don't like tumbling the 1/2" tanks, but you know, everyone dealt with them before, so why are some kids getting so snot-nosed and spoiled these days. What a bunch of whining pansies. I'd get them in a heartbeat if I were you. Just take a look inside first.