Good question. I wonder if the Airtabs company has wind tunnel tests on RVs, especially ones like our ACE which has a very flat front face? Our rear end isn't a "boattail" either, though I was hoping that adding the Airtabs to the side of the "toad" would help direct the air around the both of us, treating us like a single unit, though no one would call a Scion xB aerodynamic.
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