I've got a fair bit of experience with this material. They add carbon to the mix to give it greater UV stability, as long as you stick with the black it wont fade, the brown does at around the 8 year mark. I've seen 20 year old black slabs that look pretty good still. The material is made to look like wood by giving it a wood grain surface texture, I'm pretty sure this is done by injecting a tepid plastic mix in to a low temperature mould, which as it hits the outside surface cools rapidly and drags making fine streaks. Which is fine except the bit near the injection spout stays hot and so you get a really smooth piece which you don't really want on show as it just looks naff and will often be mixed in to your order. If you can, make sure you get the supplier to cut it, not only is the stuff dam heavy but its a nightmare to cut, its highly abrasive and wrecks any fast moving blade through the heat generated, abit of WD40 or wax as lubricant can help. Overall it doesn't look half bad outside after a year once its got a bit of green growing on it. The recycled plastic I use is made from used hay bale wrap, which the manufacture collects and washes, shreds and extrudes.
Ahh FYI, never lay it in a way where your going to see a exposed cut end. I've found metal splinters and large clumps of hay in it still.
