Well for starters, the database is powered by Navigraph. But most importantly, it seamlessly integrates with a wide variety of 3rd part aircrafts. In the A32NX for example, all you have to do is enter you Simbrief username in the flypad and the flightplan automatically loads through the cloud.
It also supports airframes for pretty much most 3rd party aircrafts.
All it takes is a little tutorial and time on Youtube and you’ll be a convert and you won’t use anything else with airliners and jets (CJ4, CRJ etc…).