I just purchased a Plano Pro Max double (not the XT) for my Tribute & Patriot and they both fit.
The singles go for 1/2 the price or less. All you get with the double is another layer of foam and some straps[:@].

The Patriot fits well, which should resemble your Switchback.

http://www.keystonecountrystore.com/Archery_Equipment_-_Supplies/Bowcases/Hard_Bow_Cases/Plano_Pro_Bow_Max_Double_Bow_Case_-_Grey/Page_1/BOC2397605.html

The SKB freedom would serve you well, it just wasn't going to work for the double I was after. Now I can carry both bows, two tackle boxes & arrows in one BIG box.