from a review...i think efficiency is maybe not that great on these?
I got this tire because the OEM Continental had issues with wet handling and a tendency to hydroplane at fairly low speeds. These tires were designed to overcome that problem. My first impression after I had them installed was that the grip and road feel definitely felt much better. As I drove home it started to rain and there the improvement was extremely noticeable. Now part of that was my old tires had 3 to 4 mm tread left and these were brand new. But it did feel better than I remembered when the car was brand new. Now that I have driven a few thousand miles on them I can say they definitely grip much better than the OEM's they replace, especially when wet. So far I haven't encountered any noticeable snow.
Now for the cons:
Ride quality is the same or slightly worse. You can feel every bump and defect in the road. Doesn't jump or effect the grip, but you can feel them.
My energy usage has gone up. I used to average about 290 watts per mile, now I am averaging about 320 watts per mile. Some of that is new tires, but I have measured my indicated speed vs actual and it hasn't changed with the new tires. We will see as time goes by. I expect to get more wear out of these than the OEMs(~30000) so maybe the cost will average out.