actually, sorry, i hate to be such a nitpicker, but BFN was not runnning of the RS engine.
they completely scrapped the RS engine and started over from scratch when making BFN. this is straight from the mouth of Julian Eggebrecht and other Factor 5 people like Thomas Engel. i can find the interview if you wish. its straight from the horses mouth.
besides, even most "casual" gamers CAN notice differences between the flight engines of RS and BFN.
check out my new post for new info and pics on Rogue Leader.