Just got back from a 3100 mile road trip, and was very happy with Forester. Good seats, great handling, low cabin noise. Average about 25 mpg which should go up as the tires wear and the engine gets a bit looser.
The engine has plenty of power and the 4-speed automatic shifts smoothly. In fact, the 2006 Forester is a sporty vehicle that is fun to drive because of its low center of gravity.
2 things that I have done to the original vehicle is that, at 500 miles, I changed the lousy OEM tires to Goodyear ComforTreds (greatly improved handling and ride and no tire noise) and I added sound damping material to the doors and the rear cargo floor. This resulted in a couple of improvements: the stereo sounded much, much better and there was a significant reduction in road noise.
Subarus have a distinct personality and you have to read the owners manual to operate the vehicle correctly.
Will probably replace the "donut" temporary spare with a regular tire spare since on a long road trip I wouldn't want to be bother with fixing a flat immediately.
Overall, the fit and finish of the car is very high and its all-wheel-drive system provides a lot of traction in bad weather situations. Also, a very safe vehicle with a 5 star rating.
Update March 2012:
Previously reviewed this vehicle when it was new, and thought an update would be a good idea. I haven't had any problems with it, and get regular service at the dealership.
Glad I did the sound-damping project when I first bought the vehicle, because the sound system is now super and the cabin is quiet at high speeds.. It's fun to drive on long interstate trips or just around town to go shopping. I feel very safe in it especially in bad weather.
Gas mileage is very good at 28 mpg on the interstate. The car handles like a dream doing 85 mph or higher. Car can get up and go, and it brakes well.
Not a lot of leg room for rear seat passengers.
Glad I bought it, and expect to get at least 250,000 miles from it if I live that long. But if I do, I will buy another one.