For programming ie: writing text files, how much does it matter? If you're doing graphical work, video or gaming, certainly monitor choice is more critical. The model numbers really meant nothing until I googled them. It appears you want to upgrade from a 20 inch to a 24 inch widescreen LCD. If thats what floats your boat then go for it. Its always nice to have a little more real estate on the screen.

My primary monitor, which I'm using now, is a Samsung SyncMaster 930B, a 19 inch LCD with 1280 x 1024 native resolution. I also have an older 17 inch Magnavox CRT and a somewhat newer View Sonic 21 inch CRT. All of them work just fine for writing Perl code.