I use SoftTH to run 3 22" LCDs (5040x1050).
It requires one of your graphics cards to be powerful, and the other to be able to receive a bunch of data and display. My system: nVidia GTX 280 1gb OC and nVidia 8800 GTS XXX. Obviously I use the 280 for the powerhouse and the 8800 for the third display. SoftTH is free, but the disadvantage is it won't work with DirectX 10 or OpenGL games (that I know of). DirectX 8 and DirectX 9 are fine, and fyi LFS is using DirectX 8.
Hope that helps, although I don't know about TH2Go...