Recently Tomas Slavik helped to organise a dual race inside a shopping mall in the Czech Republic. The results are pretty mental as you can see from the video. It was a very popular event and was even shown live on Czech TV and broadcast worldwide on Freecaster. Unfortunately due to an early crash with a 6m fall the course had to be shortened but what remains looks like plenty to me. That first Step up... Oooof.

Above is Michal Prokop race run view and with a longer edit from Matej Stapic below.

Dual Rules!