I will put my vote in for the Buicks. I currently have a 98 Skylark (kinda mid-sized) and have had no problems at all. I bought it off lease with 25,000 miles on it and currently have 176,000 miles on it. I recently added up all of the receipts I have for it, it came to under $800. That includes normal maintenance items like brakes, oil and filter changes, tranny fluid and filter changes, serpentine belt, air filters and intake manifold gasket set. The intake gasket would have been the most expensive repair if I didn't do it myself (only $35 for the gaskets, the rest is labor costs), but even that would have been under $250 to change. In my opinion, a great car that is very reliable and easy to maintain. But then again, I got more than 160,000 trouble free miles out of a Geo Metro that people said were junk.....
Oh yea, 98 was the last year for the Skylark, so maybe that's why it is so trouble free for me.....