I've had significant issues attempting to run dropbox headless on the server for file syncing. We needed to include files from another group that was used to primarily working in Dropbox in a daily report build, and so our first go at it was to just run dropbox on that machine and pull the files directly from there. Long story short, the Dropbox client crashed periodically and would stop syncing due to issues with its local state.
After setting up monitoring around the client to keep it running we wound up switching to a different, more reliable solution.
Dropbox works ok on the server but I wouldn't rely on it as a step in any important workflows unless the client has improved significantly in the past year.