I have two FF's but it is overkill, I never use a fan speed higher than "1".
But if I were to do another Sprinter in the future I would skip any crank out awning screened windows and just go with a few fixed glass ones but make up for it with two roof fans. Parked they are far more secure than leaving windows open, will close with rain sensors or no need with the Max, less sheet metal being eliminated, less area for increased corrosion potential, and can set one to suck in and the other out. For sleeping in secure campgrounds etc. I would use screens on the cab side windows if I needed any more air.
Just saying really that the crank-out awning windows are very expensive, have finicky mechanisms, won't keep wind-blown rain out, are tricky and/or expensive to install, and provide very little open area. Factory glass looks much nicer from the inside as well as exterior, and should be free-er of corrosion long-term.