In reply to BigLob:
I was out there last year and am going back over new year. There is a lot that you can do with a 60m and that's all I had last year. I did a few longer routes but with someone I met there who had a 70m rope. For the trip later this month I bought a new rope. I went for an 80m. I think in Chorro 70m would be fine, but I thought 80m might be more flexible for future trips elsewhere (plus you can trim the ends if they get worn and still have a 70m+ rope).