If I were you, I'd join RUSA, just to get their handbook. It is excellent. They say if you want to do a 1200k ride, you need to experience a sleepless night on a 600k.

I have a friend from Florida who is hoping to do the Death Valley Cup (Badwater _and_ Furnace Creek 508.) He did Badwater last year, successfully.

I think, if I were planning on doing Furnace Creek, I'd like to have a 400k or 600k under my belt just for the confidence factor.

There is a saying, though, that after 200 miles, nothing changes. If you've made it that far ok, and can maintain nutrition, etc., you can keep going indefinitely.

Still, I would rather have the knowledge that I had, in the past, ridden 374 miles successfully.

Plus, a brevet series acts as training in itself.

Nanci