My experience:

Nikon FE - sticky multiple exposure lever. Otherwise fine.
Nikon F4s - Overall good, some wear and tear but nothing ridiculous. Had an electronic fault that caused it to kill a set of batteries in about 48 hours. Sent it back.
Nikon F4s (#2) - Missing the eyepiece. Some wear and tear, but everything works fine.

I also got an EX-rated Nikon F5 that was in really nice condition with no faults visible other than some wear around the tripod mount.

Jim