IMO finding end product "similarities" between the Merc and the Acrua is a big stretch. The angles in the curvature of the two are not the same, and these differences have an enormous impact on the ultimate look of the silhouette of the car.
I never cared for (worse - I actively dislike!) the CL, and although I have some design comments about the Mercedes pictured here (too much flair over the wheel wells, for example), I find the end product of the two cars to be nothing alike.
That said, while not perfect, overall I like the design of this Mercedes. Somthing about it reminds me of an Astin Martin.
Similarly, I like the design on the 2007 BMW 3 series coupe -- which is a much more appropriately sized coupe in my opinion.