I like the CL because of all the gadgets inside the car and the business like exterior look
CL550
http://www.mbusa.com/mercedes/#/exploreOverview/?vc=CL&yr=2010&vmf=CL550C4

Cl600
http://www.mbusa.com/mercedes/#/exploreOverview/?vmf=CL600C&yr=2010&vc=CL

I like the SL because it is a convertible and the exterior looks 'racey'
SL550
http://www.mbusa.com/mercedes/#/vehiclesMenu/exploreOverview/?vmf=SL550R&vc=SL&yr=2009

SL600
http://www.mbusa.com/mercedes/#/vehiclesMenu/exploreOverview/?vmf=SL600R&vc=SL&yr=2009