RSS - where did you get the racking from in the end just stumbled across this an it looks so good the end product!!!
I ended up with http://www.buyplantlights.com/sunlighter-plant-stand-sl44.html, overall it will do its job just fine and seems sturdy enough so far. If I had been able to play around with an assembled one before purchasing I would have went a different route. There is not enough cross supports for my liking and I don't like the way the trays rest on the supports.