Sauber is of course now the only Ferrari engine/PU customer left following Marussia's demise; with Haas to come in for 2016.
All the same, there is often much talk in the media about the small teams funding the R&D of their engine suppliers through exorbitant fees being charged for supply. So where does this leave Sauber, which does not appear to be in the best of health - waiting for Haas to arrive, and hoping that nothing goes wrong there ?