I've got the tourbus10, and have it around 1/4 when practicing alone usually. I'd happily recommend it, not too many fancy features to get bogged down with as while I'm sure there's something better out there I enjoy the simplicity of being able to plug in, tweaking very rarely. Amazingly portable, I've carried it miles by hand with a bass strapped to my back, (very jealous of these car owning people). Should keep up fine in most situations, you will eventually distort it when trying to be heard over a drummer, guitarist should be fine though.
All the best, hope this helps!
Cal
P.s if effects is your thing, consider roland cubes. Would stretch the budget a bit though