Hi there! You should apply with the 680, higher overall is more important. And then if you like, you can use the optional essay to point out your slightly higher quant score on the other attempt. Did you take the TOEFL or similar test too? I believe some of the programs you list require that, as strong English communication skills are important for the intense, participatory programs like the ones you list. The Stanford and MIT programs are both very competitive -- worth a shot depending on the strength of your leadership skills -- but just want you to be aware how competitive they are. You could also consider adding Emory, USC, or Notre Dame for a slightly safer option in the US. I've heard that too about programs in Europe, but I'm not an expert in their career placements or immigration issues, so do check that with the schools, and perhaps with recent alums. You could also look at programs in Canada where that might be less of an issue - I believe HEC Montreal has a one-year program.
Good luck, and keep us posted if we can help with anything else!