Ade,
I was thinking of an odd 19" bit tight for space running three monitors. I even cut a piece of paper to represent the screen foot print of a 19", and to be honest I would not pay the extra premium which would be 2.5 times what I can get a 17" one for.
It would only be 17mm Vertical and 47mm on the Horizontal bigger measured against a 19" Diamondtron. And remember with a Trinitron/ Diamondtron you get edge to edge screen usage . And you dont have that massive Mask to stare at either. Usable screen dimensions on the P791 are 245mm Vertical and 325mm Horizontal
That said, a manufactured Dec 2001 [bought new April 2002 for £300] 19" Sony hardly ever used {I was emailing the guy} went today for £69 but it was "pick up only" in Tooting
But have a look at
ThisMitsubishi 19" very small foot print considering, £55 now but I bet it goes for ball park £100 + £20 P&P. I saw two 18 month old 19" Iiyama VM Pro 454's go for £140/ £176 respectivley as few weeks back [£238 new Ebuyer] barmy I know.