When I first read about the CLA45 acting as FWD most of the time, that was disappointing. Torque is only sent to the rear wheels when slip at the front is detected.
This little blurb sounds hopeful though: "Power distribution is fully variable: in normal driving, the CLA 45 AMG uses front-wheel drive in the interests of optimum efficiency. When the driving dynamics so require, the variable AMG 4MATIC all-wheel drive splits the torque between front and rear axle up to a ratio of 50:50 percent. The variables influencing the power distribution ratio are vehicle speed, lateral and longitudinal acceleration, steering angle, speed difference between the individual wheels, selected gear and accelerator position.
Curious how the reviews will read.