If you have to ask, I think you already know the answer... I went through the same thing. Buy the A550, you won't regret it! If you buy from Fry's, the difference is actually $500, and you can get a 5 year service plan that includes a loaner for under the average going rate online. The gimmicky motionflow and glossy screen on the A650 certainly aren't worth it. The 5:5 pulldown @ 120hz is nice, as is the better contrast for even deeper blacks, but overall it just wasn't worth it to me. The A550 is a heck of a performer for the price! It has the best color of the 40" sets that I looked at and it has no ghosting, smearing, flashlights, or other visual artifacts to speak of. The only thing that is mediocre on it is the sound. It's better with the EQ tune, but still not as good as some of the other sets I've heard. Route it through a home theater though and it's damn near perfect!