Well the RJ100 is the first with the new update. The cockpit layout and the exterior will be transferred to the other models as soon as the Update goes out of beta. It depends on what you like to fly with RJ70+RJ85 are the ones with the extreme STOL abilities. So if you like to fly to challenging airports, those are best. The RJ100 is like a CRJ900 or an Embraer170 with 4 Engines. Just a great regional airliner. I got all of them, because when you buy them separate they cost each 22$. But when you buy a package with all 3 the 2 extra planes costs 7$ each. If you want to begin to fly with it, just buy the RJ100 because this one is currently with the best cockpit and Exterior model