Very good point!!

but then you don't get remote control, or the digital DSP. On Alpiine units; when you plug directly into the 30pin connector of an Ipod, it bypasses the internal DSP and uses the D/A in the H/U for much better sound quality. You may not realize it, but the 1/8" jack on an Ipod has a non-defeatable eq that limits and enhances sound reproduction specicifically for headphones. When using a head unit, its all digital, when using a Pre-amp its all Analog, and thus open to all sorts of interferance.

I considered just going with an equalizer since I don't play CD's or the radio. Only drawback is no remote.

http://www.wetsounds.com/pages/products/WS-420.html