What about durabilty and maintenance?

Someone asked:

Maybe you could address how it stands up to rain, wind, dust, and even (ack) snow? Any problems with birds yet? What is your maintenance cycle like?

I've had this system here in southern Canada (43N latitude) for four years now, used for summer heating of a swimming pool. I had expected problems with the cleanliness of the reflectors but my experience has been very good so far. Addressing your points:

About wind: we haven't had extremes here (tornados or hurricanes) but some very strong winds indeed in the last four years and there has been no damage at all from that cause. The profile of the array is low. There are springs at the link arms to cushion the relentless buffeting from the wind. I am recommending that folks park the array horizontally during the OFF season (all winter long around here).

About dust: I had been concerned about dust from the dirt road out front but it has not been a problem since we get rain pretty regularly and that tends to clean the reflectors effectively. The acrylic mirrors are back silvered, so the reflective surface holds up pretty well. I have plans for a "cleaner" wand that will plug into the cross pipes for those times when the rain does not come.

About snow: I have been trying to dissuade folks that want to use this system in climates with snow since it just is not practical. Besides, in spite of the popular hype about solar, we don't have enough clear sun days here in the winter anyway. That's about 200 lbs of snow on each reflector in the picture (click to enlarge). It gets even heavier when the snow is wet. The reflectors suffer no damage at all from the winter.

About birds: No problems at all. I know what you mean, but I have been pleasantly surprised. The deck is another story, particularly when mulberries are in season. The birds around here LOVE mulberries and they leave droppings everywhere.

About maintenance cycle: none really, except for that time in the spring when the plants pollinate. The pollen is really STICKY. This is usually before pool season so it is just a temporary annoyance. Perhaps you noticed the holes in the hangers that let the water run out? That helps to keep the reflectors clean.