It really does depend on your application. In my domain (math research), it is substantially better. Fable can solve really hard tasks with surprising consistency. It makes mistakes, and occasionally refuses, but honestly, at the top level, ideas are the currency and the rigor is the busywork. The other models cannot come close in this domain.

If you couple Fable's idea factory with Sol's rigor, you get a real game-changer. It puts the emphasis on top-level ideas, and nearly trivialises the intermediate layers.