Thank you for the replies. I've still yet to hear them in my house, getting them hooked up today.
I don't tend to have a fixed budget for things, but rather to try to make the budget fit what makes sense depending on the available products.
If I were to pull a number out of thin air, I'd say spending $50 on a sub-woofer would be a nice amount, but if ones costing much more 'make sense' in tems of what you get, then I'd consider doing so. Usually I'd have a higher budget; a layoff adjusted that. Right now it's for two music speakers; I might hook them up to the TV I'm replacing, and they could eventually be in a 5.1 (after I figure out how to resolve my preference for the couch on a wall adjacent to the tv with the 5.1 sound being best with a chair in the middle of the room, or at least a couch opposite the tv wall).