I've been using the older analogue TH2GO for several years, first with FS9 and then FSX. I wouldn't want to go back to one monitor. There are a few things to know
1. If you use TRACKIR, then v4 or v5 is best as they have a wider field of view than the v3, this is significant as when you turn your head to the outer reaches of the left and right screens v3 loses track.
2. There's a slight narrowing of the view (vertical distance), of course with Trackir that doesn't matter too much, but I'd really like 6 or even 9 monitors (one day maybe)
3. The halo texture used for lights gets overexpanded, so a revised tiny version is needed to fix it. One of the scenery makers makes a free fix for that (possibly GEX), but I noticed someone posted a fix at Avsim this week too.
The digital version allows for continuous image behind the screen bezels, this might seem nice, but actually it's worse in cockpits as switches and indicators get hidden, much better to have the full picture and it's amazing how quickly you don't notice the bezels anyway, much like looking out of a multi-paned window, you simply focus out the frames.
Just be sure the chosen monitor resolutions can be supported by TH2GO or can be set to match, especially if using widescreen monitors.
The biggest advantage of TH2GO is in handling multi-monitors, as far as your PC is concerned is just one very wide monitor, no need to fuss with windows settings which get frequently screwed up and it's really great to run multiple programs like email, browser, Word, etc all at once, very handy.
A must have as far as I'm concerned.
Of course other options are beginning to appear now with Eyefinity from ATI and soon something similar from nVidia, but this Matrox hardware solution works very well indeed.
Allan