The F4 1000 is and awesome package. The engine has lots of power (more than any stock Duc) and the handling is superb (flickable but yet rock solid stable).
In terms of confort (ergos) it's more demanding (as more racy position) than a 999. It's kind of like a 998 in that chapter.
Defenatly tell your friend to give it a try before he decides buying either one.
Or tell him to get the two as i did
