here is my experience

benz C: quality is good. price is reseanable. No maitainance package

BMW 3 : inside is not comfortable. good for small people to drive and ride. Good maitainence deal

AUdi A4: is bigger than both above. I really like the style. I believe it is V4. So less power. no maintainence package

Lexus IS: no experience, But ES 350 is very comfortable car and reseanable price. Godd service

Volvo s80: cheaper, comfortable ride. good warranty and free maitainence( 5year, 60000 mi,include brake pads and windshield blade, oil change.). but less power and handling is not as good as benz C, BMW 3 and A4)

 

If money is not a issue, buy BENZ E350. It is new design 2010. I like it very much.