I've only ridden mine 3 times, longest being 50 miles.
To me, compared to my Cannondale caad8:
- the CLX is much, much smoother over non-smooth roads, cracks and bumps
- around 1" higher handlebar on the CLX because of longer head tube + non-integrated headset
- CLX's steering response feels a little slower than my caad8 (may just be my head)
I use the same alloy handlebar on both bikes and swap wheelsets between them. Being relatively lightweight (145 lbs) and lacking in power, I didn't notice any difference in stiffness between the two.