I always enjoyed the "Instant Action" option of Falcon 3 much more than the full-on campaign mode. Who wants to spend 20 minutes flying just to drop a few bombs and fly back home?
Although, with Flight Simulator, I enjoyed the realistic aspects. This is probably because I had no expectation of dogfights or other "action" while flying. It's the difference between sailing and going waterskiing behind a motor boat. Both are enjoyable if you're expecting the right thing.