Had seats in 320, row 8, seats 7 and 8 with my boyfriend for a Dbacks vs. Los Angeles Dodgers ball game. We didn't get to see the roof open or close but I hear the process is really cool and they play cool music during the process.

The seats were plastic and push-down, all colored green. The usher in our section showed us to our seats and told us to enjoy the game; very polite.
Everyone was friendly. If you wear your Dodgers or Giants jersey, you can have peace of mind in the cheap seats at Chase Field. The fans won't hold it against you and in all likelihood there will be plenty of visiting fans in the building as well.