I'm just about ready to buy and most likely will get the 642 and some DLP glasses. I'm tossed between the 73 and 82 sizes. At the price of the DLP glasses, I save a little money over stepping up to the 742.
But I am concerned about support after mitsi gets out of dlps, not for bulbs as I finger worse case you can buy a bare bulb an reuse the housing. But the color wheel is more concerning.