Upgraded from a CT to an IS F Sport with electronic suspensions last September.
IS pro: a lot, starting from the power of the drivetrain, to the smoothness of the drive, the confort, the handling that is vastly superior. In general the feeling is much more refined and pleasing.
CT pro: MPG, shorter and lighter
With the CT I used to have an average of 17km/l, with the IS I'm averaging 15km/l. But I'm driving much faster with the IS, I cannot resist to the hybrid power.