Mainly the price. Not sure about liftoff's settings, quad choices, and fields but yeah, the price. I don't know how the multiplayer performs but from the video I saw on youtube it looks like it will work pretty well. To note, this sim is a single man team. I don't know how much time he is able to put into updating the game. However, since I donwloaded it there has been one update. I don't know what the changes were as I am not able to see it on steam. This being said, $5 isn't a lot to lose compared to the $50 we spent on AccuRC.