Only the PH730 is capable of natively handling 720p HD content with a native pixel format of 1280 x 768 on the DLP chip. The other two is limited to 1024 x 768 resolution, or XGA. By scaling the HD content down to fit the horizontal dimension (1024) you can fit 16:9 HD content, but I wouldn’t go that route. It’s just not that good. When it comes to contrast ratio the PH730 trumps the other two with 2500:1 instead of 2000:1 for the other two. However the PH730 for some reason only pumps out 3000 lumens while the PD525PW has 2700 and the PD527D has 3000. The lamp lifetime is stated to be 4000 hours, which isn’t much, but unfortunately is standard for lamp-based front projection systems. There are development underway that will use LED backlights for DLP and other projection systems that will do away with lamp replacements.
I don’t know why any of these brands would introduce brand new products that have a 4:3 aspect ratio. Of course we use these projectors for work and for play, but even most of the notebook PCs that are coming out are wide. Go wide, that’s future-proof. If I were to guess, with Acer not being a top-of-the-line brand in the US, pricing will have to be around $1199 for the PH730 while the other will have to be south of $999, about $899?
Dell’s new 2400MP DLP projector that has a 1024 x 768 pixel format goes for $1099. Dell is a decent brand in the US and so Acer will probably need to undercut to get significant business. One of the most unusual resolutions for a front projection system must be 1400 x 1050 or SXGA+ and this is on the $2699(!?!) Dell 5100MP. Simply weird and way too much money.
FYI, according to Acer’s website here, to get a 100″ diagonal screen size from front projectors you need to be 3.9 – 4.3 meters (~ 14 feet) away.