FWIW I believe they are working on the King of the Mountain series
http://www.planetultra.com/KOM/index.html
and just have the Heartbreak (the easiest one) left to do. I believe only two tandems have ever finished this series before given the amount of climbing it has. (we are one - a slow one, but one just the same).
It seems they are very fast, and are apparently looking for more speed.