Tralyx+ Spare Lenses

The optical performance of these lenses is fine, but the photochromic process is basically one-way when it's cold out: they get dark and then stay dark until they warm up, rather than adapting to changing lighting conditions. This makes them suboptimal for late afternoon Nordic skiing, which is the prime time when I'd love to have a functional photochromic lens. I imagine they'd be great in the morning, but who wants to get up that early?