Screens are becoming less of an issue compared to what they once were and many people consider Stewart to be more of a brand name instead of an actual quality upgrade. Durability of screens from Draper and Da-Lite along with quality is very similar at a more reasonable price than Stewart.
Now...
DLP is the front projection format of choice. The theoretical level of LCD blacks is finally approaching DLP levels, but DLP has had these levels for a couple of years now. The technology with theaters and DLPs is the one to beat.
Now, how much is that Sharp actually going to cost vs. the Sony is a big question... Reliability is also a very big question. Sony is not the performance leader when it comes to projectors. Keep a close eye over the next month or two on quality for the Sony projector and look for any complaints about the projector. If at all possible, view both projectors in a show room side by side or at least in one store, then another (this may not be possible though).
Projector central really is an excellent resource to keep reading through, but you will see the difference between a good review and just a "This projector is the first I've owned and it F'N ROCKS!". Obviously, quality of user reviews runs the scales and complaints are what you should look at - in whatever projector you get.
Is DLP better? Is Sony the way to go? Am I telling you to get the Sharp?
No, maybe, and definitely not.
I have a Panasonic LCD - I love it. It is 960x540 (1/4 HD) and is beautiful on a 106" DaLite screen (manual, non-tensioned). I have installed Sharp DLP's, Marantz, Runco, Sony, Sanyo... etc., etc. I think any of the new sub $4,000 projectors you will be very happy with as long as the reliability is actually there. I would definitely wait about one more month to do research on the new batch of projectors that was just released and try to check around your area for stores that may be displaying some - or willing to display one for you to see.
I bought mine, site unseen, because of
www.projectorcentral.com about 1.5 years ago and I have no complaints. There were NO 1280x720LCD projectors at anything approaching a reasonable price at the time and DLP was running closer to 10 grand instead of under 4 for 1280x720. You have a lot of excellent choices and I don't think you will be unhappy with LCD or DLP. With LCD you are guaranteed no rainbow effect which makes it potentially better for you no matter what. DLP may seem more filmlike with richer colors though.