I'm reading here since quite a while and this post made me sign up finally.

I'm looking into building a led light with high-power leds (I personally wouldn't go for a 5mm led system), being into electronics since, well, decades. So I can compare my findings to the products that arrived on the market lately. One of the lights is the mentioned UFO, the other known to me is the procyon 100 from howngrownlights. Both have 80-100W of power-dissipation, something I aimed at for my own system, which I see somewhere between a 250 and 400W HID system.

I will have to try myself. A site testing (not selling) both of them - along with other led systems - on vegetables is maybe everybody should have a look at, if considering using leds for grow.