There is a tire that some people run here that's supposed to be almost as good as having studs....very soft, very flexible sidewall. And if you run it in the summer, it just melts away! So it can make a difference, but I don't believe minor differences matter that much.

 

For whatever reason I don't really trust these tires. They seem slick in the rain and I'm worried about them in snow/slush. I had Michelin's on my Grand Cherokee a couple years back and those tires made the Wrangler's I had on my Explorer feel like they were covered in grease.....and those Wrangler's made the Firestone Wilderness tires I had before the recall feel like they were greased.

 

No problems with my tires here, and it's been plenty wet (for a change!)

 

I also went through a Boston winter with these tires. I had no problems in the snow or slush, and really haven't had any in rain either. But on ice, or really packed snow, I felt they underperformed.

Low Rolling Resistance is really about how much the tire deforms at the contact point. There is a fair amount of extra energy required to deform the tire as you drive, and that is the energy saved with LRR tires. I've read it is up to 2 mpg, but have no personal experience with the numbers.

The consequence of LRR tires is that you generally have a smaller patch of rubber on the driving surface with the LRR tires. This has nothing (directly) to do with the rubber compound in the tread.

I've also heard that manufacturers are going to start adding a rolling resistance measurement to tire specs, but that obviously doesn't help right now.