rode video mics, which one is better!??!?

i want to know which gives better sound quality, the Rode iXY (that connects to iphone) or the rode videomic (that connects to a dslr camera). so i basically want to know which gives better quality. i own a nikon D7000 so rode mic can plug directly into it. whereas the ixy plugs into iphone. wondering which would give better sound quality which just normal speech talk like an interview, no concert recordings or anything like that. just normal conditions like indoor situations and outdoors.