I say just go for a 9600 Pro instead of the XT. XT ain't much better and it's more expensive. I'm sure your bud would be happy to save a couple bucks there. I think framerate-wise the XT only gains 10F/S and in flight sim that ain't a lot.
hehehe, I'm going to staples later to find the price onnit! who wants to play chicken with my sessna!?
Now, check this out:
yeah, not a very wide range of cards, but see how well the 9600 pro preformed with like, really high graphics settings? Your bud will find it quite the delight. Of course they only did a take off for the benchmark, so you might wanna lower the graphics settings a bit for actual play.
This test is also pretty interesting.. apparently flight sim really kills the framerate when you enable AA and AF:
you probably won't need to enable AA and AF to impress your bud with this new comp setup he's gonna get anywho.