Both of those are awesome projectors with a resolution of 853x480 pixels.
The InFocus is said to be a bit brighter than the H31 but the H31 is suposed to be quieter and look a little bit better. For the money, I would go with the H31 which can be had for around 1100 bucks online from authorized dealers.
Now, that said, a projector like the Panasonic AE-700U is a 1280x720 pixels projector. It has about twice the resolution of the H31 or 4805 and when compared to the InFocus SP7205, shows even less screen door effect and ability to pick out individual pixels on screen. Other features it has over the H31/4805 are optical lens shift which lets you pretty much position the projector how you want it. As well, it has a 2x zoom lens which pretty easily lets you put the projector a good distance away from the screen and mount it on the back of the wall in a room.
It comes in around $1,800, but the doubling of resolution and added features make it totally worth the extra money if you can swing it.
Likewise at $1,000ish you have some dealers with the Sanyo PLV-Z2 in stock which is being liquidated right in that price range. It is also a 1280x720 projector with lens shift, but lacks the image quality of the AE-700 and the versatility in the install.
Which is best? Nope, no good answer. At $1,000 I would be questioning whether I wanted the Z2 at 1280x720 or the H31 with DLPs excellent ability to handle all other aspects of video imagery with excellence. In the end, I recently bought a AE-700 after seeing it at a friends home, and have to agree with others who say that this is singularly one of the best valued projectors money can buy right now with outstanding image and great setup options. Are there good ones for less? Yes, are there better ones for more? Yes. A lot better? I'm not sure about that, but better, yes.
