Should i choose new game or continue with evil karma?

[El-Sublime-]

I've finished the game on good karma and now i want to do the opposite. However, when i choose a new game, it says i can "continue" with evil karma (i've never played with bad karma) or create a new game.

 

What's the difference? May i choose continue with evil karma? Because i read that it gives you an incentive or something, but i don't want to complete the whole game again without the trophy.

[KittenKittenYAY]

I think that's detecting your trophies from the first Infamous game, if you finished that with evil karma.  So you should be OK to "continue" with evil karma (and get the incentives) and still get the related evil karma trophies.