I managed to do the Burma Road loop (Aviemore) plus the extra bit round Rothiemurcus and Ryvoan Bothy. Had it on 50% for the big climb then eco for the rest. 36 miles and it ran out of power with two miles of flat tarmac remaining. Happy with that although being at the Bothy with only two red lights remaining was an anxious time.
It goes from 5 lights to zero much faster than 10 to 5.