Mixed is best... you get to see a lot more of what the artist is capable of, how their style works etc etc. I mean, I LOVE looking at other artists sketches, and frankly I feel that I'd be more inclined to buy a book of sketches and lineart rather than completed pics, but mixed is better.
Devious Comments
Mostly because I find lineart/sketches very pretty - often prettier than the colored version. O-O
But as someone else mentioned, it's really nice when there's the original lineart next to the final, colored, version.
I also think having some sketches/lineart gives more "warmth" to the artbook, so to speak.
Success Recepie *w*
I mean, I LOVE looking at other artists sketches, and frankly I feel that I'd be more inclined to buy a book of sketches and lineart rather than completed pics, but mixed is better.