Both, really. I have the 120tpi version, and they're quite sluggish compared to any summer tire, but that's not really surprising considering the tread and studs. I've been using Compass tires for warm weather, which really are supple, and the Gravdal's can in no way be used with that adjective. I generally run around 55psi, if I recall correctly, and tweak it depending on what the conditions are like on any given day.

I'm not saying that they're bad by any means--they pretty much are exactly what I want in the snow and ice for a utility cycling tire. But they're not something I would ride just for fun.