I've made my position clear. While I do think the Home Cinema 8100 is one of the best home projectors priced between $1000 and $2000, the Epson Home Cinema 8500UB is worth the extra. First of all, there really isn't anything that the Home Cinema 8100 can do better than the 8500UB, except save you some bucks, and perhaps a touch better dark shadow detail.
With dramatically blacker blacks, that alone is enough to rationalize the cost difference. Throw in respectable creative frame interpolation, and it solidifies the advantage. Two projectors - basically what they put on the screen looks about the same - skin tones, general color handling, etc., so it comes down to how much more you will be to go from "very good" to "best" (under $4K) in overall performance.