To answer a few questions, the Dunlop SP31 is a new tire in Dunlop's line. It has a special tred pattern, very different indeed, to create low rolling resistance to help increase gas mileage. A lower rolling resistance, helps the car by putting less of a load so to speak on the engine. So far, the tires seems to be good tires. They do well in rain and fairly well when cornering. I haven't seen any reviews yet and I have only been driving on them for almost 1,700 miles but the seem to be good tires, and I think they def. help FE. I suffered a flat tire a couple hundred miles ago, here is the link to the thread which might help a little more:
I hope this helps.