I'm trying to decide which setup would best suit my needs. A dual 20" ACD setup or one 23". I will be using them on an Intel PowerMac, using the machine for digital photography (Aperture and Photoshop CS), Writing, Light graphic design, Studio MX 04, the usual (iTunes, Mail, iCal, ect). The 2 20" displays come out cheaper then the 23" in New Zealand. Which do you think is the best suiting what i am doing at the Mac?