Bought with 60K miles almost 3 years ago as a replacement for another 850 totaled in a very bad, single car accident (flipped after hitting a tree) where I walked away without even a bruise (no one else in the car with me). Now just over 172K. Average 25-28 mpg in mixed driving (75% hwy).I would absolutely buy another Volvo but for the maintenance. I have not had some of the most common problems (rear main seal oil leak, AC cond, ABS/TRACS unit), I have had plenty of problems that cost too much: rotors, O2 sensors, tie rods, ball joints, air pump...will probably replace w/ Accord, even though the Volvo is just a lot of fun (when its working). see brickboard.com for common problems/solutions.
SAFETY, fuel economy, possibly the most comfortable seats found in an auto, just enough oomph to be fun
Overall RELIABILITY - too late as 1997 was last model year and the S70 (which was just an updated 850) was replaced by S60 (totally new car).