My whole playing concept and ideal tone have become much more rock-oriented than when I was last gigging regularly a few years back. I'm not slapping at all, I'm using a pick about half of the time, and I'm dialing up my FBB for maximum grind--a role which it is quite happy to fulfilll. As I approach getting a head to match the well-used but fully-functional Eden D-210XLT that will be coming my way this week, I have thought about what type I should get. I have a budget of about $500 for a used amp, and while I've been leaning toward something on the order of a Peavey Firebass, a 250-300-watt Trace Elliot, or perhaps a GK 700 or 800, I have seen a few Peavey Alphabass and Mesa/Boogie D-180 tube heads in this price range. I am young, strong of spine and shoulders, and live in a one-story dwelling, so the weight of an all-tube amp does not cause me to flinch. Nor would I worry about cutting through: in a medium-volume rock situation, I am quite sure that 150-200 watts of power into a quartet of 10s (I plan to obtain another D-210XLT when I have the chance, or sell the one in order to finance a 4x10 of some sort) will be plenty loud as long as the signal is sufficiently distorted. My question is, aside from the problems common to all-tube amps of every variety, what are the drawbacks with the Alphabass and the D-180? In particular, would I have to run these amps so hard to be heard that I would need to replace their power tubes more than once a decade? (That's expensive, yo, and my cash flow is much more constricted--for a variety of reasons--than it was when I was a undergrad.) Those of you who have owned or at least spent extensive periods with either or both of these amps are welcome to contribute your thoughts.