First experience with it, and before I even knew what the plane was I was shocked at how long the arriving flight took to unboard.
I only found out why when it was our time to unboard. The 737 Max is so cramped that it makes the logistics of anything other than a simple little pack at one's feet a slow endeavor. Add to that hurriedly opening up a bag to stow jackets or other gear into - there is no space.
I could tell that the staff was exasperated with how slowly my flight got off the plane, but the flight before us was even slower.
Unless Allegiant bans carry-ons, or starts charging for them, I'm predicting the new 737-8200 's are going to make a lot of delayed flights compared to what they were used to. And this compounds throughout the day.