Loses...
If Revan will ever stand a chance its going to be later then that when he recovers his memory and then even with some heavy assumptions it can be doubted. Revan as far as we can proof however will not beat Exar Kun. He might or might not be able to do so but there are to many unknowns to say that he will win.
And btw: This thread has been done about 20 times... Do a search for it.