In reply to patters: I reckon you would wear down the Katoolah spikes pretty quick running on road if it wasn't deep packed snow. But when the spikes wore down you would be left with something that looked like the Yaktrax. I wore my Katoolah micro spikes inside out (spikes pointing up) one day running over kinder in hard packed snow and they worked pretty well!
You wouldn't want to wear Katoolahs on an icy pavement with no snow though, very sore on the pressure points caused by the spikes.