So I got tired of doing my tempo runs/ road races (5k-10k) in my Nike Structure Triaxes as they're a little heavy. I went out today and picked up a pair of Kinvara 2's to use for my quicker runs, but still plan on doing my long runs and easy days in the Nikes as I've heard the Kinvaras don't hold up too long, and in general I need quite a bit of support. I had a lot of trouble deciding between the Kinvara 2's and the Nike Lunaracers, as the Lunaracers are billed as a racing flat, and the kinvara more as a minimalist training shoe. What do you LetsRunners think of the Kinvara 2 as a racing shoe?