Originally Posted by
_knot_
You are better off trudging through story mode. The monster levels in story mode DO scale according to your level. The faster you complete Normal Story the better. Plus after completing story you'll get access to more clothing choices, Modules, Open Missions and more! Or you can always hop online with some fine folks on the IRC and do some leveling.
So, to answer your question: Any open mission with enemies 20-30 levels above you is good for exp. If you have the DLC, Gamega is always 10 levels above you.
Hope this helps!
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