I drive in central-coastal California, so I can't speak to handling in snow. In rain and dry conditions, I find that their performance has been adequate, no complaints. Likewise on the other criteria, (which I rated "average" just to satisfy the requirements for posting).
My comment concerns the claim that they "improve fuel economy".
I am very conscious of fuel economy; I bought the Prius primarily for that reason.
I have been keeping obsessively meticulous records of my fuel usage and calculating my overall economy.
My records show my mileage with the original-issue tires, my overall mileage, and a separate calculation for my mileage since I replaced the worn-out originals with these.
I'm finding that I am getting slightly (about 2%) worse fuel economy with these than with the original-issue tires.
I know, 2% isn't much, (did I say " obsessive"?) but, still, it's in the wrong direction...
And, yes, I regularly check the pressure and balance of my tires.