Just tried this on a level 40 barb, getting about 1.3m/h.
Down side, sometimes he gets stuck going up the stairs where the mobs are behind the catapult (destroyable) but he doesn't destroy it... Just keeps trying to run pass it towards the mob behind it and hence gets stuck.
Down side, sometimes he gets stuck going up the stairs where the mobs are behind the catapult (destroyable) but he doesn't destroy it... Just keeps trying to run pass it towards the mob behind it and hence gets stuck.