I ultimately went with the Asus PA248Q, it offered the best mix of cost and features. I can't percieve much of a picture-quality improvement but widescreen definitely has some nice benefits for development and gaming. The USB3 hub is nice, and one of the things that sold me on it, though I haven't used it much yet as I don't have any USB3 devices. There's definitely some backlight bleed and I sit close enough to the monitor that I get that light gray LCD distortion thing, but it's only noticeable with dark scenes in a dark room. It handles scaling very well--I'm running it at 1440x900 due to game text-size issues and it looks fantastic, and on "4:3 mode" it automatically picks between 4:3 and 16:10 based on the input signal. It has a 1:1 mode but I don't use it as the text and UI elements are just way too small. An interesting feature is an on-screen grid overlay which shows inches, centimeters, and a few other things and can be adjusted with a hat switch (which is also used to navigate the menu). I occasionally do design stuff and having an alignment guide will be really helpful.
No dead pixels as far as I can tell, very responsive too. So I'm pretty happy with it, hopefully it will last me a while.