I agree with Pottsie on Revan. Revan was, as Kreia put it "like staring into the heart of the Force itself", owtte. We know that the Jedi like to train their kids from about birth. Furthermore, it is implied that Revan was not yet a knight, or a very newly created one during the Mandalorian Wars. Revan also was trained to some degree by each of the Masters. He might not have had direct experience, but he had absorbed a lot of experience of others by the time of the Mandalorian Wars. Certainly, I think that he was about 22-ish at the time of the MW.
The Exile I think was older, but not very strong or distinguished in the Force. I imagine he was about 25 for the MW...