>>1405802>I'm honestly a little skeptical since it's free. There's some catch, right?Yes, you will get only as much refund as you have to pay for it.
I don't think there's any tutorial in the game, so you need to know what you are doing (it's simulator, not a game).
As for being free, it's GPL software (like Linux, etc.), the license requires it to be always free and anyone can contribute.
I have played it only years ago, when I have been teenager, and the only other flight sim I played was MS Flight Simulator X around similar time (and War Thunder more recently), so I don't know how it compares to other sims of its kind nowadays.