Couple of things that decides the recommendation:
1) Gaming, work, simple browsing?
2) Can your GPU handle dual or triple monitors?
3) Budget available?
4) DVI or HDMI?
5) Bigger the better? Functionality? Size of desk or setup area?
Personally, I would love to have 3x24" monitors. Got an LG 24" monitor with height, swivel, and tilt adjustments. Make it landscape or portrait. Not bad for gaming (as I don't get eye fatigue very much) and with the swivel into Portrait mode, got an immediate setup for stock trading if I want. Only problem is they don't make this model anymore; got lucky and a friend found a brand new one for $100 that I could buy. The ones like this go for about $200-300 apiece now.