I'm not really a fan of Dell stuff either (I've fixed more Dell laptops and desktops than just about anything else in the last four years of my computer business.) However, their monitors are something completely different. The professional monitors and ultra sharp monitors are beyond anything else that I have compared them with, especially at their price range. We have ordered dozens of the Dell Professional monitors, and several of the UltraSharp models for our sign shop, and never have had an issue with one.
HDMI is, as explained above, pretty much equivalent to DVI the only difference being that it carries across audio as well. In some situations, I've actually seen HDMI have weaker display characteristics than when connected by DVI. If you're looking for the best design connection, you will probably be interested in Display Port, not HDMI. Display Port is becoming the industry standard for ultra high definition connection with professional devices. Hence why most professional nVidia Quadro and AMD FirePro graphics cards have DisplayPort outputs, and why most professional IPS displays have DisplayPort inputs.
