I've got a Dell XPS 13 and need to get an external monitor. I am going to get a Dell since I have a $150 gift card. I'm looking between the 20 and 23" range. Is it worth it to get the "full HD" at 1900 by whatever resolution or is the 1600 enough? I really want the USB ports built in but everything above 20" with full HD and USB ports is way out of my price range or I could get the new 21.5" full HD or a 23" with USB ports but only 1600 resolution for about the same price. I don't do much gaming or video just some moderate photo editing. Any advice?