I don’t know about looking by serial number, but any used 30” is going to be severely diminished in its backlighting capabilities, isn’t it?
CCFL dim with use, and the last 30” was made in 2010–five years ago. Unless it has had a backlight replacement (good luck) or is nearly brand new, it probably won’t be very bright.
I hate to say it, but is 16:10 really that important? Why not grab a 27” Thunderbolt or Cinema Display (or wait for the standalone Retina)?