I agree with Xenon. I have my primary TV which is my Samsung LNB52750U and I love it, use it for daily TV watching...but I also made room in the budget for the HD20 for the home theater room so I had options. I love watching movies and playing video games on the HD20 at 105 inches. It makes such a difference. Most of my friends seem to enjoy the HD20 rainbow free, and prefer playing games or watching blurays on the HD20 vs the LCD TV. My wife prefers the regular LCD TV because she doesn't like always being in the dark in the theater room.
The HD20 even does fine with the lights on, but looks so much better in a light controlled room. For the price, the HD20 is a great alternative to your regular TV. It makes movies special, like they should be. We rarely go to the movies now, instead opting to wait for the Bluray to come out so we can enjoy it at home without talking people and overpriced food.
If you can afford both, I say go for it. You wont regret it.