I am very tempted by this as could be my challenge for the year. This does seem like one epic effort though!
I've never ran anything like this, but have really enjoyed my running over the last 6 months upping weekend runs to 16/17 miles. Entered the White Peak marathon in May which could be a taster.
Would I be better getting some longer efforts in this year and maybe have a go next year, or just go for it?
Cheers.