Don't know about the A O Smith torches, I'm a Victor fan myself as their parts are easiest to find around here, but the best regulators I've ever used were Smith (dual diaphragms)They maintained more consistent outlet pressure, especially when the tanks get low, than even the Victor dual diaphragms. You'll likely end up with single diaphragm regulators, & they will work OK (especially for hobby/infrequent use), but I'd suggest you get in the habit of checking your gauges ofter during use. Don't expect to get more than 5-6 years out of the regulators either.
I picked up the Victor look-alike knock-off kit from one of the mail order catalogs (JC Whitney, Norther, etc, don't remember) 16-18 years ago for something like $89.95 on sale. Everything except the torch & tips has been replaced at least once (& this thing sees very little use). The torch however, has been bullet-proof.
I saw that torch kit in the Craftsman catalog just yesterday (when it came in the mail). I didn't think it was a bad deal, & didn't look into S&H costs (if any), but I think I can do better piecing a "kit" together.