I understand where you are coming from, but I can tell you, since I own a Sharp 20k, that the brightness, and especially the black level on the Mico50 are a huge step up over the Sharp.
I suggest you find a way to see the projector in person, before you choose to go by one reviewers specs.
On your point about the second generation LED's, I wouldn't expect much change from newer ones, as these are quite bright, and equivalent to the 200w UHP bulb that you find in most comparable projectors today. In fact you would have to open the iris all the way on your Sharp 20k, and put the bulb on high, just to match the brightness of the Mico 50, and then the Sharp would look really bad next to it.
If you want a 1000 lumen plus machine, you will probably have to wait for a 3chip version.