The JVCs that use the SD card and flash drives can run up to 1GB. However, many have the auxillary input in front, which you can use with a $6 1/8" headphone-style jack. Works really great.
Go to:
http://mobile.jvc.com/main.jsp for more info on JVC stereos. The touch-screens I had and my DVD player have a 7-band equalizer, which is nice.
In my experience, Kenwoods and Clarions have poor power for really cranking it up. I usually turn mine up between 35 and 50. Sound got poor on the Kenwood around 33, and Clarion up to around 40. 45, don't even think about it, tons of distortion.
JVC, Pioneer, Alpine, and Eclipse are about the only ones I'd stick with.
Past 6 years my stereos have been:
Road Gear (old $100 Wal-Mart CD player)
JVC KD-S600
JVC KD-AR8250
JVC KD-LHX500 touch-screen
Kenwood KDC-X579
Some other JVC CD player
Some Aiwa CD/MP3 player
JVC KD-AR5000 touch-screen (favorite)
Clarion DXZ855MP full-color touch-screen
JVC KD-DV5100 DVD player (current)
Not to mention the others I've installed or just messed around with. Old Pioneer DEH-4000 in my grandma's '90 Camry with stock speakers sounds better than the Kenwood with Clarion components.
