If you have only one screen, will you use widescreen or regular? If you have a 2 screens, which setup will you use? two regular side by side or 2 wides top and bottom? If you have 4 screens, will you use wide or regular? The problem is really, when you watch/scan, work on one trade and use the eye's edge to monitor another stock. Are you more comfortable watching one point, or moving eyes around? For me, I have eye glasses. It is difficult for me to see to move eyes, so I have to move heads. So I preffer regular screens, so without moving, my eyes can cover more spaces.
I personally have all Dell widescreens, primarily for resolution. No negative effects what so ever.... Scanning Left to right is a more natural movement, therefore I prefer my monitors side by side, looking up and down continously is tough on the neck... I currently have 2 ea. 30" and 2 ea. 20" monitors and I would need to rotate my head almost 180 degrees. so I stacked the two 20's one one side. (I don't use the upper monitor much for trading, primarily for outlook and to "park" documents) 2-monitors - side by side 3-monitors - side by side 4-monitors - stacked 2x2 (<22")
With your problem, you would be doing your eyes a disservice by using widescreens. You will lose a good % of real estate by choosing them. 20" wide is only 1680x1050 while the non wide is 1600x1200. However, if you want to go bigger, than you have no choice but to go wide. I hate the wide for trading.
http://elitetrader.com/vb/attachment.php?s=&postid=1631204 I have dual 24" widescreens side-by-side on my desktop and an external 22" widescreen monitor connected to my laptop. Wider is better I even considered connecting the 37" HDTV as a monitor, but that would be overkill.
It really depends on how well you can scale... All the software you use for trading... For high resolution and wide-screen. Everything thing I see is CUSTOM which scales perfect... Except TWS that scales OK. So I have 4 monitors... 4 x 24" LG (1920x1200) all horizontal side-by-side on 2 computers running dual monitors. So I have 2 x 3840x1200 of sceen area. Plus a few side monitors for special purposes. IMO this is better than quad... Because 2 computers can run a lot more STUFF efficiently. More than this would be overkill... Because I do not run any charting software (charts are pointless)... Just look at a lot of quote data along with proprietary numbers. Once you go hi-res... you never go back.
I have 8x20.1" normal screens and it works great. personally I wouldnt use widescreen unless I'm using at least 6x24" or 4x30" and put them side by side in a portriat mode fashion, that way I dont need to use double decked screens and look up to see the screen.
My main trading computer is Sony Vajo notebook with wide screen and high resolution 1920 x 1200 px. I think it can easily substitute two 17" LCD monitors. Normally I connect second monitor to notebook to have wider desktop (notebook LCD + 17" standard LCD). But when I am traveling somewhere where I have not second monitor, the only notebook LCD monitor is fine for me, too. You can see screenshot of my chart setup on this main notebook monitor only here