Some problems I have had with this car is that occasionally, a valve will stick, but that is pretty common in 850's. also recently I had to have my clutch rebuilt and resurfaced, but now, the clutch works great. another thing that is a problem with this car (not to big a deal for some people) is that there aren't many upgrades for it.
This car handles great stock. add some new springs and shocks, and a strut bar, and its amazing. its pretty quick for a NA engine, I have added a few things to it such as a new exhaust system and a better air filter. these things really help the performance of the car. I reccomend this car to anyone getting it for a first car, its safe, and reliable, and it gets really great gas mileage.
I have read somewhere,a Volvo users page, that Mobil 1, is good to use because it is thinner than other oils.
Also try Castrol GTX Magnetex 5w-30 as used in Ford Zetec engines which are also known to have sticking valves.