I've used dual monitors, both 4:3 and 16:9, and even one of each, and I was always annoyed by the 'bar' between the monitors, which seemed to be always exactly where I didn't want it. I haven't tried it, but I think a single 27" or larger (with many pixels of course) would be better than two smaller monitors.
For the last part of my tenure with SW, back in 2010, I had IT remove all the corporate crapware from my SW computer and put it on an older surplus machine, so I had two computers and three monitors on my desk.
Mike Halloran
Pembroke Pines, FL, USA