Welcome aboard. This is the place to get great advice.
I came from a background of using a gas grill all my life and a horizontal offset charcoal smoker for the last 7 years. In some ways I find the temperature control as good or better than the gas grill over a far wider range of temps. The longest I used to go on my smoker was 1-2 hours before I had to go play with the vents. My first brisket on the Egg went 10 hours and I made one and only one tweak about an hour before finishing. I'd opened the lid and the temperature was 5 degrees low when it recovered. It was so stable I kept running outside to check that my Maverick ET-73 remote read thermo hadn't lost synch. But yes it was that stable.
You are gonna love this grill. I am already planning on my second Egg right after Christmas.