None really that I can think of off the top of my head.. Not going to compare the old 5d, never had one, nor any other 1d series camera although I can imagine seeing how they’re both relatively older cameras (1ds iii 5d) I’d assume that the 1ds iii would win over that one.. I’m wanting to get rid of both the II and the 1ds III for another 5d III.. Quite frankly the 1ds has seen two owners and the mk ii is becoming irrelevant as well and I have no desire to own a 1dx.. I have a 60D as well but generally not worth noting other than it’s flip out screen is kinda cool..
but to be honest as stated above: A real advantage? I can’t think of one.. It’s an older camera I still use because the IQ for all intents an purposes is somewhat similar and has a menial advantage over the mark ii in frames per second on continuous drive mode .. as far as using it in darker conditions? nein. it does have more af points thereby allowing me to select a wider area but really that doesn’t mean anything to me, i do fine with the 9pt in the mark ii.. but really the REAL winner is the 5d III.. So for whatever you reasoning in asking me instead of just looking it up; if you’re in the market for a camera, I’d suggest selling your crop frames and use the money toward a mark iii.. but other than that i’m all O_o about it.