Depends on the crowd, if its a rockish crowd, they probs won't like rap but who knows

Personally I loathe the stuff
i'd say not for your first gig. You can experiment once you've done at least a few but stick with something solid and try to get some sort of a name wherever you play before you try something like that. I can see that blowing up in your face much more likely then everyone loving it.
I think it's a good idea. This way you get to do the cover your own way instead of just copying what's already been done. Just make sure you do it well.
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