What's your motivation for even wanting to swap out the components?
I have an '08 Madone 4.5 with a triple. It's new to me, so I don't speak from long experience. I love it. I was out in howling wind a few weeks ago on a "recovery" ride. Glad to have those granny gears that let me keep my cadence up and my HR down.
The shifting on that bike is smooth and fast, too. Stick with the triple unless you have a good reason to switch.