The HD70 is a couple hundred cheaper and puts out a little better contrast-4000:1 and only 1000 lumens. But the HD65 is putting out 1600 lumens and 3000:1 contrast. The HD65 is new I believe. I have not seen either one in action since I am deprived of a good AV store around my area. I have heard the HD70 was a great performer for the money. I want to upgrade my Optoma 739. I am not opposed to other brands, but want to stay under $1500.

even though the contrast ratio seems better on paper with the HD70, the fact that the HD65 puts out more lumens means it will generally have sharper overall contrast, you have more flexibility on how far the projector can be placed, and the relative darkness of the viewing room.

in an area with virtually no quality av stores. I just bought a Pioneer Elite VSX-92THX receiver and now have the bug to upgrade the projector, etc. I need to buy a screen anyway and it may be the best time to sell my existing Optoma 739 projector. It seems to bring around $500 on Ebay, plus I have an additional new bulb. I would guess I would benefit by upgrading to the HD model/720p. I figure it would run me around $400-$450 to upgrade.