I am not from Laminar Research; just a flight simmer.
If you download the demo version found at http://www.x-plane.com/desktop/try-it/ you can test for yourself.
You will be restricted to a specific airport in the USA and will have a time limit once you have setup your flight.
I am not a Mac user. Be aware that XP11 is heavy on resource use and will generate a lot of heat. Your system may crash due to overheating.
If it all works, and decide to purchase X-Plane all you then need to do is apply the product key supplied at the time of purchase as the demo version is the same as the full version. No further downloads required.
Have a look at the system requirements found at http://www.x-plane.com/kb/x-plane-11-system-requirements/ Many flight simmers build their system that exceeds the "Recommended Requirements" to get a good performance.
Good luck and welcome to the world of X-Plane.