Before this, I came from a Ridley Noah.http://ridingagainstthegrain.com/2012/04/21/ridley-noah-review/
The Madone is much, much lighter...by several pounds.
faster when spinning up to speed, likely because of the light weight.
faster in crosswinds as well...I'd be really curious to compare actual wattage, but I don't have good controls to compare to from the Ridley.
The biggest change? Composure. There is no flex in the Madone, much like the Ridley...the bottom bracket and chainstays transmit 100% of your effort into tractive force. But unlike the Ridley, the ride isn't coarse. The Ridley transmitted ever pebble up the seatstays into the relatively massive integrated seatpost. The Madone, either by virtue of the different carbon, spindly (brake-free) seat stays or smaller seatmast, does a much better job of dampening vibration, road noise, potholes, cracks, etc.
No--maybe the lightness is the biggest change.
After my first ride on the Madone, I came back to the bike shop, and the first words out of my mouth were "you can feel all of the lightness that they added to the bike." It sounds stupid, but it's true. You can feel every ounce of lightness that they "added."
I think for now, I'll keep it as-built, and as things need updates, I'll keep weenieing in mind (e.g. when it needs new housing, etc.). I love