Unlike many here I don't have a OS X device. My PC is custom built and runs off SSDs mainly. The two external hard drives are mainly for longer term storage and back up and are traditional disk based. It boots Windows 7 and I use Ubuntu in a VirtualBox.
I use 2 24" monitors (one ViewSonic and one BenQ, bought at different times). Not the best monitors of course, but my priorities are elsewhere.
What is important to me is the keyboard and mouse though. I use a Leopold FC300R (Cherry Blues) mechanical keyboard and a Razer Naga (back from the days of using Eclipse and needing all sorts of fancy shortcuts). To me the mechanical feedback of the keyboard and the fair ergonomics of the mouse seals the deal for me.