Ok, so what I think I've come to a conclusion about the two, and I just want to verify if I'm right: 1. Loud noise or hum seems to be a problem with ABY switches bc the signal is being split and the culprit is usually a ground loop, non-isolation, and a myriad of other problems for splitting the signal. 2. There doesn't seem to be much information online about just plain ol' AB switches. Is it subject to the same issues as an ABY? I've seen many AB switches on the market that feature no ground lifts & isolated transformers, so I assume they are indeed NOT subject to obnoxious hums. I currently use the Radial Bigshot ABY which works great between my Orange OR15 and Billm modded Blues Jr, isolation transformer and ground lift eliminate the hum, b/c there definitely was a loud piercing hum before. I find myself never ever ever using the Y, I just really need an AB (for the most part) and plan on getting one with a small footpring like the JHS mini AB, Loopmaster or Analogman, of course I'd keep the Radial, just in case.