I need to replace my Logtiech z-540 system (sub/amp blown), and I'm thinking maybe I don't need surround anymore. So, I'm looking at the Logitech Z-2200 and its replacement, the z-2300s. Anybody heard both of these? The z-2200s, if I can find them, have a $50 rebate, so they'd be in the $50 range. The z-2300s, obviously, have no rebate, and they're in the $110 range. Wonder if there's any real difference between the two?