First of all, Consumer Reports sucks. Instead of just reviewing one aspect, they review toothbrushes to toasters to automobiles. So because of their broad category, there is no specialization and they usually do not know what they are talking about. Bottom line, Consumer Reports sucks at reviewing everything, particularly cars. Their 0-60mph tests are slow, they bring up stupid points, and their reviews do not explain much...they are just not car people.
As for the price, I think both companies are just about even. A fully-loaded C320 4Matic and a fully-loaded BMW 330xi both equal out to around $46K - $47K. As for the other classes, the price for Mercedes can get very high when they are fully loaded, but one does not need to get all the options, such as the $3,000 Distronic Cruise Control system, or the $2,000 hands-free mobile phone kit. And if someone is looking for a really sporty luxury vehicle, the AMG models are a great alternative to BMW's M offerings (key word being "alternative").