Hi, I've been playing open mics (think fools-on-stools type of events with acoutsic guitarists) lately and I'm tiring of carrying around my 800RB and accompanying 112 cab, as I live on a large, cold, college campus with no car, and occasionally have to walk about a half mile from my dorm to the "venue." So, I'm looking for a combo amp that won't break the bank or my back, but will be audible against 2 acoustic guitars and vocals in smallish rooms- cafes and the like. Used is preferable, for the sake of my expenses, but if something is a really great deal, I wouldn't be opposed to buying new. Right now 1x8, 1x10, and 1x12 combos seem to make the most sense, but I worry that the smallest won't keep up and the largest will be tough to carry. Is 1x8, 1x10, or 1x12 best? What do you think is a cheap amp and easy carry for low-volume open mics?