I thought I'd chime in with some usage reports, impressions, etc., on the Sharp XV-Z30000.
I bought mine early last summer, about 16 months ago or so. I'm still on the original bulb. As of this morning, I've put 1730 hours on the projector and the bulb life is at 14%. Much to my shock/delight, I have seen no noticeable dip in brightness. I do not have a light meter so I'm basing this observation solely on my eyes, but dammit if she doesn't project a beautiful, bright picture! This projector in combination with the Darbee and my Da-Lite High Power 120" screen, pumps out a picture that is more-often-than-not, STUNNING. I run the PJ on all the full-brightness settings. It's ridiculously awesome. Blu-rays in particular, shine on this setup. I usually demo "Art of Flight", "Prometheus", "Avatar 3D" and the first 10 minutes or so of "Oblivion" which is nut bar. The PQ is sharp (albeit softer on the edges), the black levels are solid despite my addiction to all things bright (that's coming from a Kuro owner), and the color accuracy, to my layman eyes, looks exceptional.
Regarding gaming: I read a bunch of reports of gaming latency on this PJ prior to purchase and I assure you, it's a non-issue if you're a gamer. I beat Dark Souls 2 on this PJ. That should say it all.
I bought 2 of those cheap Chinese lamps that Zombie10K informed us about last year for replacements and haven't had to crack the PJ yet to install one yet. I'm curious what happens when I push this lamp down near 5% and lower, if I'll see a noticeable drop-off in brightness, and if the bulb goes out, is there any damage done to the PJ? I think I'll probably replace the lamp around 5% just to be safe.
All in all, I love this PJ. My family loves the PJ. My friends hate this PJ (because it's not in their home). The Sharp XV-Z30000 has brought hours and hours of enjoyment to my family, neighbors, kids, you name it. 1730 hours of enjoyment in fact.
I see no reason to upgrade until 4K prices drop. For now, I'm in Home Theater Heaven.