Steve, I might suggest looking for a good 126-bodied diesel--the diesel version of the high-line sedans from the early-mid 80's (the correct dates escape me at the moment). Significantly newer technology along with all the MB virtues; like any MB, expensive if not maintained by the book, but otherwise good and solid with the usual characteristic that the expensive repairs are usually those that last a very long time. Also, significantly more rust-resistant.
'97 SL500, 40th anniversary edition
'04 Olds Bravada (SWMBO's)
'06 Lexus ES330
'89 560SL (sold)
SL--Anything else is just a Mercedes.
(Kudos to whoever said it first)