No, really, I've never worried about watercolours lightfastness, probably because I've never experienced fading from a watercolour. What I have personally experienced are drawings done with markers that disappear with the sun and also fountain pen drawings that become pale shadows of what they were. But as for watercolours, I don't personally remember any of these mishaps.

You know, I have bought this http://clap-san.deviantart.com/art/Kiss-the-Autumn-127739116, the original, for mere 60 € shipping included (from Vietnam!) and I would have gladly spent thrice the sum for it. And I placed it inside my cupboard, too, along with other posters (no naked men, however, even if you just gave me an idea).

About time: there are also authors who employ three+ days to complete a single page, don't despair ;)