Just how universal are universal guitar/bass cases?

[bowling-name]

Hello. Not the sexiest gear acquisition thread topic, I know, but I am searching for a couple hard-shell cases to fit my first guitar, an odd-shaped (sort of explorer-like) Washburn A5-V, and my favorite bass, a superb 'mojo'-infused Ovation Magnum III.

Do you think those universal cases would work for me, or am I going to have to buy another Ovation Magnum III with a hardshell, then resell the instrument?

Thanks,

--ryan