Alrighty diodes came in and got it all soldered up! It turns out it was worth my time everything is working smoothly and since my two diodes are to220 it doesn't seem they will even need to be heat sinked. The board gets warm but in no way hot now. I also went carefully through with the multimeters and variable power supply to gather some new numbers.
Again this is the newer single board unit that Deal Extreme now ships with D1 and D2 replaced with to-220 case diodes 10a:
I am done with these Ithink, I have also been reading another forum where they go far more in depthon the design and use; and it seems to me that they are a hit or miss. Theconcept is great, but they just seem too cheaply produced to trust to a $12 led.I like them even with 3 modes because the low mode is pretty good, but thestrobe isn't quite fast enough and the PWM is just too slow. They are also toolarge for most applications, so I would have to already have the lights in handin order to be sure that one of these would do well in the application. I haveused them in a single XML application and had good success for a short periodbut the led stopped one day and I blamed myself for perhaps hitting the ledwith something, but I have found that these are much more resilient than that.I had an XML-T6 come loose from the board that it was mounted on (due mainly tothe fact that it seemed like they didn't even solder it in place, maybe somekind of conductive paste) I just let it sit around. Over 1 year later afterdoing a stent in my tire well in the trunk of my car and after being stuck inmy soldering kit for a month or two; I decided I would try soldering it to acopper board that I had sitting around, astonishingly it still worked.
True, as the input voltage and output voltage neared each other I did have better efficiency , but if you notice the board temps, they kept getting higher too. At the time I tested it, I was more concerned with the inductor getting hot, but the diodes were very warm too. I was measuring with an infrared thermometer and I don't recall exactly the hottest spot. There is going to be a break over point where efficiency starts dropping again, it will be interesting to find out what it is.
Try SKU: 128269 it seems to be the same to me from the pictures, and by the way people are talking they have been sending these for a while instead of the one originally listed in this thread.