Also - keep in mind the DS100 is modular. You can purchase a dual monitor arm and then upgrade it to a triple. Or buy a new base. Or a longer pole. Or buy your own pole (1.5" OD Tube, not Pipe).

The LX System is not something I have much experience with - but it seems to be a bit more flexible when it comes to adjusting up and down.

Honestly though, once you reach a certain point - you move your body around rather than move the 100+ lbs of monitors.

Or just setup the monitors correctly at the right height to begin with.

If you want to do this cheaply - take a look at this:

http://www.plastk.net/highres/24mon/

These guys over at VT seem to have used some cheap MDF board to get the job done. Clever and cheap - just watch out for MDF that contains formaldehyde and other nasty ingredients. Most of them do, surprisingly enough. Quite toxic to inhale when milling it - less so when it is sitting around.