I would drive them all and buy the one you fall in love with and can afford. Personally I would look into buying a used one for the huge discount off new and maybe step up in size to a 5 series or E class. My vote: 328, C300, then A4, and last the G37. I have not driven them all but I did not care for the G35 sedan I tested with 20K miles. I really liked Flu’s analysis.