I took the marathons out tonight for a little spin... found a couple super icy patches and tried my hands at stopping on them at speed... a little hairy but i stayed upright. there were a couple of spots where there was relatively hard packed snow and the tires handled very well on those.

overall they feel like they handle well on pavement and on the rough stuff... obviously they have yet to be put to any real test but so far they seem pretty decent...

it took a bit of fudging to get them to clear the fenders but that probably has more to do with my setup than the tires - the fenders are rated for 28s max and these are 28s... both on a frame that wasn't reeeeeeeally designed with fenders in mind.