Im discovering how my clean channel breaks up on my tube amp and quite like it. I would like more break up to hear how it sounds but volume is an issue. So I thought about an attenuator. I know you can buy them from the gutar store but what about the ones you see at an electronics store that are less money? Any experience with those?
Those attenuators are made for dimmers and other devices where impedance is not a consideration. Some people have used them successfully, but I would go ahead and just assume it's going to turn your output transformer into a pool of molten iron sooner or later. They're less money for the same reason that cling wrap is cheaper than condoms. Same idea, but...not really a good time to be frugal.

The good news is that making your own attenuator is not terribly expensive, and pretty simple. I'd choose that route if you want a decently cheap one. Weber also makes some inexpensive ones that are even cheaper used.
The problem with attenuators is that if you don't spend a fair amount on them they tend to affect tone. I would suggest you have a look at a Rivera Rockcrusher, not sure of your budget, but I have one and tone isn't affected too much at all. slight compression and tighter bass end, barely noticeable unless you're out to hear a difference. Or if you can find one, get an Ultimate attenuator by Magus Innovations, best attenuators ever imo, cant hear a difference in tone at all, unless you're a dog or somethin'.