I've had them on now for about a month. (
Pics of them on my Elise here). I have mixed feelings about them. They are plenty sticky, at least out of the gates, but you certainly lose a touch of responsiveness / crispness in the corners. I kinda regret not spending the extra money and going with the 888s.
On the other hand, these tires are sooooo much better at displacing water and avoiding hydroplaning than the stock Yokos. Of course, that was to be expected with the deeper tread. And, speaking of the tread, I personally think it is quite aggressive looking and looks nice on the Lotus, if you care about that sort of thing.
Alas, if I had to do it all over again, I would have gone with the 888s. By most other accounts here and elsewhere that's probably the best tire you can put on a Lotus.