The iPod is an excellent means of accessing music when on the go. Unfortunately, it's not really an audiophile product because it doesn't offer a digital output and the built in D/A is adequate, but no better. Despite that it's still an excellent product well worth the $300-500 dollars they sell for. I use a 30Gb model and after experimenting with uncompressed AIFF files I eventually settled upon AAC 192kbps mono files as my preferred file format. It works wonderfully in the car with no sense of compromise in such an audio-adverse environment.
I believe some of the iRiver products have digital I/O.
I believe some of the iRiver products have digital I/O.