I am in the market for a new head. I run a 8 ohm 2X10 and a 8 ohm 1X15 sometimes both at the same time for 4 ohms total and sometimes only one for 8 ohms total. I figure most head will pull that off. I currently see a good deal on a SWR SM-500 ($599), and a eden WT-400 ($649). any opinions on those or another amp in that price range. I am looking used I figure I can get the most for my money that way. thanks.