I fly most of my flights using the built in ATC. I truly enjoy the real world procedures as I am currently taking an online ground school for Private Pilot and Instrument.
I want to say the built in ATC is good but you really have to respect IFR flight planning and rules. Otherwise, you will be fighting the system. Bottom line, you need to know what you are doing in making official flight plans. I have tested the built in ATC thoroughly, it works pretty nicely so honor the EFB’s arrival airports runway suggestion. After all, that is the active runway. Start your flights before selecting an arrival airport. Then, build a real world flight plan in the cockpit and honor the rules.
Sure, there is room for improvement especially in regards to taxi information corresponding to real world charts or being able to ask for deviations to the east or west around weather and other bells and whistles. But if you know what you are doing, your flights will be better with the built in ATC. If you do not know what you are doing, then do not use it because you will be fighting the system. When you fight the rules, ATC will constantly correct you or get confused. So if you are going to use ATC, fly like a pilot. It’s a challenge and real fun.
I use a console so I use the built in ATC and I really look forward to performance improvements for ATC and improvements to interactions. But right now, I can use it successfully to fly all kinds of routes and even do the same approach over and over again successfully with ATC. I can even sync the Microsoft ATC with Simbrief and PMDG. Simbrief is good, but it is better using the runway selection found in Planner.FlightSimulator.com so I match Simbrief to planner. Then, my PMDG FMS syncs with the built in ATC and the simulators Live Weather. If you work hard, it will generally work for you. It’s all good fun. Thanks for listening.