I still try to use original music and from what I've seen and done, should someone have made a vid before me, I just hope to miracula that my vid would come out just plain better
[and thankfully, multiple vids I've made has had people 'famous' make vids as well to the same song and from what I've seen, I think I did better

But again, if you think you're sure to flunk and your vid would just end up being a "ripoff" then guess what, it already is before you even made it...
I'm surprised that when I started the Feel the Rhythm series, I hadn't recieved flak from any of the ddr project people seeing as I was using the WAYYY ahead ddr songs... But in the end, I liked the vids I made to those ddr songs better than the ones made on the earlier ddr project vids.... But that's just my taste, nothing too spazzy or anything...
So just make the vid damnit! It's no longer feasible to say "oh no, maybe it's not original..."
DBZ + Linkin' Bark anyone? Nobody's gonna stop them, why should you stop? ^_^