Without a doubt, the Cannondale Synapse Carbon Disc has a great specification. It does come with a price, but it also comes with a with a full Ultegra Di2 (the only alteration is the HollowGram crankset) and with hydraulic disc brakes for superior wet-weather braking performance.
The carbon used for the frame, says Cannondale, is the BallisTec: that is the American company's method of high-strength, high-stiffness construction of the carbon frame. After many years from my first rides on the original Synapse, this frame remains as one of the best ones I have ever ridden.
Being picky, though, the wheelset you'll get with the Synapse (Mavic Aksium Disc) is good, but not great. It's ok for everyday use, but doens't quite match the standard of the other components on this bike.