I've used both Dells ("regular" and UltraSharps) and Samsung, and have been impressed by the quality of both. My friend, who does photography as a side job, says that true color reproduction is not accurate on either Samsung or Dell, but the Dell is much closer to being true. I can't tell any difference, but my Samsung (SyncMaster 220wm) looks more vibrant to me.

My Dell monitor had 8ms response time, and my current Samsung has 5 ms...I've never noticed ghosting with either monitor so I think you will be fine with either 5ms or 2ms.