It depends, it can also just be a crappy adaptation. I personally like this piano version: http://www.youtube.com/watch?v=jd-h0debytI&list=UUl3iv3e...

What stingraycharles said. It depends on the adaptions. I liked this one by the Ohio marching band 110 Gangnam style

http://www.youtube.com/watch?v=cDficEfonAE

It makes you realize how bad the synthesized instruments they used for it were... also not arranged for an orchestra. You can't just simply take the original note for note and play it on different instruments.