Depending on the gig, I've been using a Peavey PA (600 Series), with either 2 Cerwin Vega 15" speaker cabinets or 2 off-brand 12" speaker cabinets (plus a small powered spot monitor).  Sometimes, in an attempt to conserve setup space and have less pieces to connect I've been using my Peavey KB300 (a heavy amp).  Since my one-person-band  brings with it the one-person  carry in, setup, tear down, carry out, I'm looking for a good compromise of weight, size, complexity, and sound quality.  Any ideas?