I have been playing for a couple of years now, and am ready to purchase a new amp. I have been using just a practice amp. What should I start looking at? A combo or head/cab stack? What brands should I start looking at? What about speaker size? 12" or 15"? What wattage? I know these things depend on what I use it for so... I play hard rock with a progressive edge to it. I like a dark sound but do need some clarity. Most of the music I play is riff based. I don't gig (yet) I just write with a guitar friend of mine. We do record though. We are looking for a drummer to write with and possibly start looking for gigs with so I would like something with enough power to do small venues. As far as budget, I dont really want to spend over $500. Thanks for any direction you an give me.