[Dkennel]

What is your budget?
If you want German engineering you could consider a V6 Passat, I hear the new one is pretty neat. Of course you have no bragging rights or elite appeal with a VW. Audi may be a little better option if you want/need that. BMW has the highest luxury appeal right before Mercedes. Mercedes are ok but pretty expensive and the c-class is very small.
As far as bang for the buck I think you could not beat a VW Passat V6.
I have never been a fan of Lexus (souped up Toyota). Infinity sedan (g50) looks neater to me.
One of our other cars is a Jaguar s-type, pretty neat car, relatively cheap if you buy used (texascarsdirect.com) in Dallas, but definitely reliability and maintenance issues.
Well that is my 2 cents, enjoy looking around and comparing models.