Depends largely on whether you rest on the page as you draw (so you need quick drying, or you'll smudge) and whether you do anything over the outline; obviously a non-water resistant ink won't stand up to a watercolour or ink wash.
I like Platinum carbon for drawing, personally, although it can wreck pens if left in them (I use the Platinum carbon pen). It dries reasonably quickly, and will stand up to watercolour.
EDIT: This might be a useful link;
http://artistsjournalworkshop.blogsp...ountain%20pens
Bookmarks