I work with Q2 Dell 2408's and can attest to the productivity increases for photo/video editing and stock trading. Sony Vegas Pro is extremely customizable, allowing multiple adjustable screen set ups to be stored as presets depending what I am working on. Think or Swim and Options Express can be opened simultaneously on different screens, so I can use the features I like in each in tandem or trade both accounts at the same time. My preference would be to be able to spread tabs from each one individually, like having a chart on one screen and an option chain on another in the same program, but neither platform is very user friendly, and I have been in too impatient to get trades on in the heat of the market to figure it out, even though I should.
I have been a multimonitor user for years, previously using Q2 19" CRTs in tandem. My main monitor facing front and my second monitor is angled for peripheral view. Two monitors of the same size facing forward does not work for. I'd rather have one single large monitor, and do Windows 7 style snapping.
The only complaint with my current LCD set up, other than taking up lots of horizontal space, is that most of the programs automatically restore down on my second screen as soon as I work on a program on my main screen, and I am always having to expand again and again. Never had this problem when using CRTs under XP. The programs stayed put and did not minimize automatically.