In reply to marky:
It'd be difficult to rap off, so a 50m single would do. I must admit we took 2x50m half ropes, but only really because that's what we had. I think as far as the 80m single is concerned, I'd hate to be rapping down that thing hoping that 40m would reach... if you see what I mean.
The 7a pitch is just a crimpy affair, nothing like the main pitches. I suppose you could aid it.
Take some water.
It's most definitely a walk off. The evening before we did it, Mrs J went for a run and put our trainers and a bottle of water at the top. Luxury.