The sound will be good, but obviously not as good as CD. The iPods can actually sound very good as long as you use high bitrates, preferably in AAC format or Apple Lossless format (although the latter takes up stupid amounts of space).
One thing I would recommend is an in-line volume control, you can get them from Maplins for £3.99. Unplugging my BeoLab 4s from my laptop produces a pretty darn loud pop, but this in-line volume control did away with this issue.