The Dell monitors are top of the line, not to mention their warenty is impeccable. I'd also note the 24"ers are a lot cheaper, the 30"ers are amazing and have a great resolution, but anything in between is generally overpriced and has a low pixel density (which may or may not be a bad thing depending on what you are doing with it.)
Personally, I'd rather (and have done) get two 24"ers than one 30"er.
But, if you can afford the 30"er and want to go with a single screen, I'd say go for it, they are amazing. The 26-27"ers, less so. I'd say go with a 24"er which is the same res.
So, in short, I'd say one or two Dell 2408WFPs would be your best bet, I love my 2407WFP, and the 08 model has HDMI which you wanted. Mine has been amazing for a while now, the monitor did break (the on-off button broke, the actual panel was fine) and they cross-shipped a new one out to me almost instantly, so I was back to working in no time. The stand is amazingly customizable (something you appreciate when you have it) and other nice features like the card reader and plethora of inputs make it a brilliant monitor.
If you have the money, 3 x 24in is insane.