Whats a WUM? :lol:
It's a fair question, they look pretty similar at face value and they're both set-neck and double cutawat.
The Fib is semi hollow, apart from a center block it's empty, the pickups are super low output, it has a 12-20 radius and of-course a maple top whereas the Briggs is a solid plank of hog with fairly hot pups (duncan custom custom and alnico pro 2) with a 5 way.
It all seems to adds up to a big difference tone wise :)