I saw one being sold for 15K and thought about getting it, but the throw length isn't right for my room and it would probably burn a hole in my wall with the brightness. It will accept 4k native media, but some of the reports are that the upscaling to 4k from 1080 is pretty darn nice and the advantages can be seen, even on smaller screens. Seeing the 4k Sony projectors in the local movie theaters is very impressive to my eye, very nice combo of blacks, color, sharpness yet with cinematic film like quality that pretty much puts CRT finally to bed. The theaters are probably using 4k material, though, of course on large screens.
Cinephiles are spending a lot more than 25K for what seems like a lot less projector, but I suppose the ability to calibrate is always demanded at this price point.