Lokie - for my project, I'm probably going to need 200'.
If that changes, I'll let you know.
(& yes, it'll probably be better than your Walmart cables.
I will tell you though - as an experiment, I spent $13 on 18ga speaker cable at Home Depot, and did the same thing I'm going to do with the better stuff, & it sounds unbelievable for the $$. Now, there is A LOT of labor involved, but still -- you'd never guess you were listening to $13 worth of cable.