Scratch-
MS CFS2 is a blast! Graphics, sound effects, flying models, everything. It kicks!
Once you get bored with the missions included, you can download new ones from multiple places on the web. Some very clever people have put together some really challenging ones.
Another thing, you can download totally new aircraft too! Keep in mind that the game engine is geared to single seater fighters, but I have downloaded a B-25 bomber and TBD Devastator and TBM Avenger torpedo planes. The torpedo thing is harder than you think to program remembering that MS did not include that functionality into the program. Someone has created a mod that allows you to fly along (preferably below 50ft), drop a torpedo, then watch its wake as it speeds towards your target. Of course, watching it can be fatal if you just launched against a Japanese carrier. (Did I mention the flak? And shells whistling past you as you get targeted?) Watching those torpedoes go boom when you hit is extremely satisfying though.
Only drawback- no online play. But you don't notice that, the game is very functional.