how long you willing to wait?
I bought the x35 last year, and even that is enough for me to wait the 5-10yrs until there's affordable UHD projectors and real UHD content(not just some high resolution, but bit-starved online crap)
if you're in the market for a projector soon, I'd absolutely go the e-shift route now. I simply don't think there's a good reason to buy into anything UHD right now. it's far too early, we don't even have a 100% finalized idea of what UHD will be, aside from the resolution.
if, on the other hand, you're not really in need of a new projector, and you can wait 5 or more years, then might as well wait. buying an eshift projector now just delays how soon you'll be able to afford a true UHD projector later.
Displays: Samsung PN64F8500/JVC X35
AVR: Pioneer VSX-1018AH, 5.1 audio
Sources: HTPC(Mediabrowser), PS3, XBOX360, Wii, Sony DVP-CX995V
Control: Harmony One