I have a 1996 Toyota Avalon with 177K miles on it. My mother-in-law bought it new, and I bought it from her at 95K miles. The dependability factor is extremely high... it has rarely been in the shop beyond regular maintenance. I love the smoothness of the drive. I'm reminded of how smooth it is when I occasionally drive a different car.
For such a large sedan, I get great gas milage... about 28mpg around town.
What continues to impress me, though, is the leg room in the front and back. I don't often get to ride in the back seat, but each time I do, I make the comment "Wow, I forgot how much leg room is back here!" Even with a 6ft tall person sitting comfortably in the front seat, other adults can still sit comfortably in the back. We have taken many road-trips with our teenagers, where there were 3 in the back. None of them felt too squished.
Another big plus for me is the trunk size. It's huge, even in the newer models.
If I were buying another sedan, it would be another Avalon.