You can go to the SAMSUNG site and compare them side by side.
As you move from the 450 series to the 950 series the contrast ratio's get bigger and the resonse times get shorter. Plus starting with the 6xx series it has 120 mhz motion flow.
What the site will not tell you is this. Starting with the 650 the screens are glossy making the picture better but reflecting light. However the 630 which they just came out with has a matte screen like the 450 and 550 series making it a better choice for bright rooms.
This LCD is on the top of my list for a purchase soon. But what are the advatages of one model # over the next e.g. 550 ... 650 ... 750 ...850? What am I getting for the extra $$$? Are the picture, color ,contrast and brightness qualities all the same and the higher model #s have more bells and whistles? And what about the 530 & 630 series ? What sets them apart from the others?
Thanks for your reply in advance and all others please chime in with you 2 cents ... as I am trying to gleem as much info as possible for a purchase later this week.