When I purchased my 2016 Crusader 315rst it only had the single air conditioner. This unit comes with ducted air and if you purchase a new unit with both air conditioners installed at the factory both will be ducted. If you add a 2nd air in the bedroom to a unit which did not come from the factory with two air conditioners then the bedroom air will only blow in the bedroom. This is what I was told when I purchased mine. So far I have been satisfied with the performance of the single 15k air however I am investigating the addition of a 2nd air. If I add a 2nd unit it will be a low profile unit and the most quite one I can get. Hope this helps.
Kevin & Denise Griffin
2015 Ford F350 Super Duty 6.7 Diesel CC SB, Demco 18K Hijacker Auto Slide, Pace Edwards Electric Tonneau, TST TPMS 507 Standard Sensors, Titan 50 Gallon Midship Fuel Tank
2016 Prime Time Crusader 315RST 5th Wheel, Dometic Slide Toppers