I got a 4 GB black shuffle, and I'm pretty happy with it, it serves as a supplement to my 160 GB iPod Classic, I use it for working out and biking, because it's much more lightweight.
As stated above, the clip is a fingerprint magnet, and scratches very easily (I think it's made from the same metal as the backplate on iPod touches). The iPod itself hasn't scratched yet, in fact it's holding up pretty good.
Also, on the nano vs. shuffle-thing, I'd go with the shuffle, but that's just because it suits my needs better. I had a 4G nano, that I sold once I got my classic, because it couldn't hold all of my music anymore, and I find that I'm syncing my shuffle more often, so that I listen to only the music I currently like/work out to.
I hope that made sense.