Current UHD pricing is outrageous. Certainly not worth it, unless you are driving a Ferrari.
However, once the price drops way below 10k, I will be getting a UHD projector. Hopefully next year. At my current, THX viewing angle I can almost see individual pixels (and a screen door of course!) UHD would certainly make sense for me.
P.S. And once I buy a UHD projector, guess who I will be calling for calibration?!