I'm replacing my old, outdated (but still working fine) Pioneer HU with a Sony CDX-GT610UI HU. But I have a few questions first: This HU has 1 set of RCA plugs on back for output to a sub/rear and two more RCA's for BUS inputs for a changer, sat.tuner, ect. It has controls on the frt. panel for sub/rear speaker level. I assume that these outputs have to be high level outs, right? Can they drive a small (6 or 8") woofer enough to give me some low end response? What about a set of 6x9's? or will I have to have an amp? The HU also has Ipod control, but I use a Sansa but the Sansa will take the Ipod plug, does that mean it'll work or is that feature useless to me cause I will not buy a $ 200+ Ipod to play mp3's. when my $ 60 Sansa does great!" IT also has a front USB but the user manual say's nothing about a size limitation 256 mb., 1, 2, 4 or 8 gig. thumb drive?