Just for fun I shot the RX100 against my 1D X in best video mode on each. The 1D X held a bit more in the highlights, nothing to jump up and down about.
All in all bugger all in difference, of course the Canon has the interchangeable lens FF sensor advantages/disadvantages, but honestly the 50fps and stabilisation in a camera that fits in your hand is good to.
yeah the RX100 is pretty amazing for the price and size. I bought it primarily for the 50fps / video quality.
to Gel; u should only post constructive comments, this is a great forum for helping you grow as a photographer, if you want to talk smack do it elsewhere.