My previous trailer was a 36ft box style with one 15 air unit & a MaxAir bedroom fan. All in all it did ok, so when I bought the AS25ft I figured one unit was more than enough & that monster 50 amp cord was another factor in the decision. But like I said in the original post, I never figured in how the aluminum would conduct & transfer heat. It's not an awful situation here in mid summer but cooling down takes a while. Like a previous poster mentioned I too immediately turn on both fantastic fans along with the air for about 10 minutes to get things started & that helps. However next summer we'll be in Las Vegas for a couple weeks & that heat will overwhelm my single unit.
2016 FC 25RTB
2016 Nissan Titan XD Cummins Diesel