I tested all the cars mentioned above in AWD form, plus a few more (Subaru LGT, Volvo T5 AWD). The Germans were overpriced, underequipped and had horrid interiors. Plus I hated MBs attitude when I asked to test drive a c230 4 matic like they were doing me a favor. In the end it came to the g35x and the IS250 awd. I chose the latter for it's smooth ride, quiet interior, and better fuel economy. The IS may not feel as road worthy as the 3 series, put it turns in some of the best slalom times in it's class.
BTW, I have owned American and Japanese cars for 13 years in a climate as bad as Boston, and I never had a blower failure, or any of the problems you listed.