Sometimes I kill the Jedi masters easily, sometimes they kill me easily. It's hard to see any pattern there, as the game is supposed to spawn them to suit your character's level. Maybe I put too many points in non-combat areas in the beginning.
But yes, with Vrook in particular, I often have to use regular attacks, plus all the shields and boosters I have.
<{POST_SNAPBACK}>
Vrook was very hard, because he always used force heal. I really had a problem with my Consular, because I was on my first planet and had a very low defence.