I have a Dell 2407 and it is tremendous. I cannot begin to explain how much this screen is a step up from the Acer 2223WD it replaced. Mind you, I got it with a giant employee discount. After selling the Acer I only forked $180 out of pocket for the Dell, so I don't have quite the same perspective on price for it.
The Acer 2223 isn't a bad screen at all, but the colors on the Dell are so much more accurate, and for someone that spends so much time in Photoshop when home, it's really worth it. I also used to use a 21" Dell flat screen Trinitron tube, so the 2223WD was a step sideways at best. I lost 150 vertical pixels and it always bugged me, but with the Dell 2407, 1920x1200, so I'm ahead of where I was.
I also agree with your assessment regarding size. Anything bigger than 24" is simply too big to be very useful for most people, programmers excepted when it replaces two screens. I sit very close to my screens.
The other great thing about some of the 24" monitors is that they have various video inputs, like S-Video, Component. I have my Xbox 360 hooked up via VGA and it is great for that too.
I'll sum up my impressions of the Dell. I've had it for the better part of 2 months. Every time I sit in front of it, I think, "I love this screen."