Stienman kinda touches on what I was getting at. No matter how wonderful your blades are, if you run them back and forth across an irregular icy surface, you'll scar the blades' wiping edge, which will lead to streaks. Some blades have a secondary wiping edge that's stiffer to try and shovel snow/ice out of the way when the blade is leaning over further than usual, but that's one of those "features" that may or may not actually be worth the extra money. It's probably just better to chip the ice off yourself, apply enough heat to melt what's left, and then use your wipers to
wipe the remaining moisture from the windshield.
That said:
Silicone blades will resist cracking and stay soft much, much longer than any rubber blade.
"Beam" blades have an inner rail that maintains the downward bend to force the blade against the windshield.
Covered/sheathed blades help prevent ice/dirt buildup that would clog the hinges which allow the blade to flex during use.
All of that being said, take a look at blades like the
ANCO Winter Extreme, which claims to have all the good-for-Winter features.
--Patrick