We have a 2012 RL. We replaced the original fan under warranty because the blades were interfering with the slide. We run it on the medium speed and are satisfied considering the situation. Because it is so close to the ceiling, you're not going to get as good a flow as you would if it was lower. There isn't much room above the fan for it to draw air.
Roger & Cheryl Full Time since 2002, RVing since 1975 2008 Chevy 3500 Crew Cab Dually, 2012 RW 36RL