It's always nice to have good pencils as source material. That's one of the great thing about the different comics clubs here on dA - you get pro-level pencils that you are allowed to ink for your portfolio.
Too true on that and the great part is that if you talk with a lot of the artists ahead of time and build a relationship with them and are up front about what you are doing most times they will give you permission to ink or color their work. Currently (scratches head thinking) I have permission from at least 20 artists a lot of them pro to ink their work or color it.
Exactly! I think it's really great. As a newspaper cartoonist (and someone who recently returned to dA after years of inactivity) I think that it's turning out to be a wonderful resource. Since I've started to go to comic conventions and the like, I've decided that it's important for me to pick up (or practice, rather) some of the more traditional comic art techniques that you don't often get to do when drawing newspaper strips. This site has certainly started becoming a great resource for that.