I was at the Hershey show this past fall and looking into the smaller trailers and several dealers said to me that the 13,500 roof unit will keep you cool in the summer but the window unit at 5000 btu will not keep up in the high heat. Also there have been a lot of complaints with the window units leaking (including the condensate finding its way in)and in smaller units it sometimes takes up valuable space(like above a frig. I ended up getting a coachmen clipper with the roof unit and am glad I did without worrying to stay cool. Also with the roof units they are placed in the center where you can direct the airflow front to back, how do you direct the airflow from a window unit when its at the front of the trailer?
I was not referring to to popups but the same trailer as mine with the same toilet and no special base. I was just letting the person know to check the size of the tanks as some salesmen never mention it especially when I was shopping for one, sorry you took the joke thing offensively!
Make sure you check the tank capacities. We have a Coachmen clipper 17bh and it has 25 gallon grey and black tanks, some competitors only have a 9 gallon black tank which is a joke. Also the roof air units will keep you cool while the window units are less in btu and can't keep up in the heat and have leaking issues.
BIGGEST PROBLEM with RV's is POOR QUALITY CONTROL and they don't seem to care. I purchased a brand new motorhome years ago and had 5 pages of problems, I repaired 99% of them and spent over 40 hours in labor. It's a shame because its the one thing that can be controlled and save a lot of disappointment and frustration. And it is not limited to any specific brand, you just has to be a well informed buyer and do all the research the best you can. That's where this forum helps. Also mine was the last one built before the Thanksgiving break, production really slacked off. I finally got fed up with it and sold it and am happy with my new little trailer.