Anyone use plastic lumber in any of their projects? I've heard that one has to be careful about direct sunlight because UV might weaken the stuff. I've also heard that it can be used to build decks and patios. I imagine that the plastic lumber used in the decks and patios would then be capable of the same things as the wood normally used in those projects. Also rot and and mildue are not issues. Has anyone used this stuff? What do you guys think?