There are decent reviews of the high-end LED DLP PJs, but most of the pubs ignore the low end pico DLP machines (LED or otherwise). People here are (rightfully) upset when a $1500 1080p PJ cannot map the pixels 1:1. Given that, the review pubs are unlikely to spend too much time quantitatively evaluating (a time-consuming process) a PJ that uses diamond shaped mirrors. I have no idea if the black levels are really good or not... I'm sure they are with a pure black signal, but if there is any (non-black) content on the screen, the LED will be lit, and all the limitations of DLP tech come into play. I'd love to see a .65" DC3 LED machine with good optics, but my guess is that is still a >$5K machine that would have trouble matching a sub $3K lamp-based PJ. Given that 4K is coming, most enthusiasts are unlikely to drop that kind of cash for the primary benefit of not having to replace lamps, thus no manufacturer has one on the market... it is certainly not a technological challenge, as it is done on pico and .95" DMDs, purely a business decision.