Originally Posted by
Rowan
I'd also check to see what the requirements are for the ride you are doing. In randonneuring, there is a requirement to have two lights for the rear and two for the front, so that if one fails, you have a back-up. Obviously, you don't need to have both going at the same time. And you do need a stash of batteries that fit both your front and rear lights, whatever you use; the run time in cold weather can be quite hard to judge.
So far, I see no requirements posted but they've released limited info. But both Mr 1200k & Cycling Heroine have ridden this double before (and are riding it this year, but I think Mr 1200k is riding it Sunday so that he can ride a century on Sat). So they will probably know.