Two different things I'm thinking right now
1 - Great idea
2 - I think you're full of it.
Let's hear that mix
If you take Bitflipper's advice and take the iPod to the HiFi store, keep the mix as wav.
I hate iPod headphones personally. Mostly because I have to listen to the idiots on the bus blasting terrible music into their ears and I can hear it perfectly fine from 10 feet and on a noisy city bus.