I have two 1725 motors,a 1/3HP and a 1/6HP and use 6" wheels with no problem.I had the fellows down at the shop find me a 110V motor that turned 1725 rpm, seems to do the trick. Mounted to my work bench. The Beall stuff is great. I opted for the 4" over the 8" pads, thought maybe the added size may drag down the 1/3 HP.
I've had most of mine for 2-3 years although some of them need to be replaced. I run them through the washer and dryer every so often--when the old woman ain't around. You should pick up a wheel rake to clean your wheels with every now and then.I know it dependent on use but how long do you get out of a buffing wheel before you reorder. Six months, nominal use?