erikamae - Thanks !
Celestial fox - It depends alot on the scale of the work and the delicacy. The best example I can use to explain would be the gnomes playground (first piece in this thread).
The foremost tree's were inked using a faber castel black marker ( has both a thick and thin end which I love ), just because its faster and looks bolder in the front helping with depth.
For the background trees though and any other background elements I would use an ink nib to get the detail in small spaces. I tend to ink with an ink nib in my sketchbook as well. I might use a ball point pen occasionally for really delicate parts like sometimes on faces just because I can get more control that way.
Largely though I do all my inking with a nib. Also with waterproof ink incase I need to paint again after.