Just out of boredom, I searched google today just typing in "The Force Unleashed Sith Lord" and I got this on some site I forget the name of:
"If you thought Sith Master difficulty was a breeze, complete the game once (any ending will do) and unlock the Sith Lord difficulty. Let's see if you're still smiling after that!"

This person got the 2 difficulties switched around, because...well, here's my little story: I first beat the game on Apprentice, full playthrough for each ending, then I did Sith Warrior. Sith Warrior wasn't a challenge at all, but at least if you just stood there, you could die, that's how easy Apprentice is. After those 2 difficulties, I went straight to Sith Master, the hardest setting that must be unlocked. I skipped Sith Lord thinking there wasn't a big difference and I'd get the 2 achievements from beating Sith Master, killing 2 birds with 1 stone. OH MY GOD Sith Master is hard, I'm stuck at the first junk-monster thingy on Raxus Prime still. That was a few weeks ago. Now I started playing Sith Lord beacause I don't think I'm gonna beat Sith Master anytime soon. And it's much, MUCH easier.
So I'm gonna have every achievement except for beating Sith Master, around 1120g i think, total being 1220 if I remember correctly.

Tell me what you guys think on the difficulties!

BTW: I'm playing on the 360, which is obvious if you read everything

It's fine, it's good they have a challenging difficulty.

Off-topic: Why do people care so much about achievements for?