I've been toiling over what sort of head I am in need of. For awhile I leaned towards a GK 800RB with a Sansamp in front, but more recently, I've found myself considered finally taking the preamp/power amp route. I don't have much experience with this type of rig. For a power amp, I've figured the QSC RMX 850 would be a good deal. The preamp is what I'm moreover concerned about. Here is my criteria: I need a versatile preamp. I want something that can give me a good fat, rock sound, but also a fat, round low end with chrystaline highs. Can anyone with experience with the RBI chime in? Or am I better off looking elsewhere, or would the 800RB idea satisfy my needs?