This is my general view on "designer cross breeds" (or "designer mutts" to be a little more editorial and a little less charitable)like 'labradoodle', 'peekapoo', 'cockapoo', you name it (spanador is a new on on me.) In a nutshell, since a Spanador isn't a breed at all, there is unfortunately no real answer to your question.
A good definition of 'breed' is to say that if two animals of the same breed mate, the offspring will all predictably and consistently resemble the parents in appearance, size, temperament, etc. This takes not only many, many generations and carefully selective breeding to achieve, but also a *starting point*. The desired traits of the breed must be selected, standardized and universally applied to achieve an actual "breed." Then you can discuss what to expect from the puppies, because a standard has been selected, carefully directed and applied, and achieved.
The only of the currently-in-style designer crosses that has even begun to organize, cooperate and create a potential (someday) breed is really the cockapoo.
So, to your question...When people choose to breed, say, a Cocker Spaniel and a Labrador, the litter often doesn't even match among siblings let alone have a predictable look, set of health characteristics or temperament. What will the dog look and act like as an adult? No one can really say. Will it have energy like a Cocker? Will it have the hip problems of a Lab? We'll have to wait and see.
Not the answer you wanted I'm guessing, but really it's true. Good, consistent training from the start can go a long way toward a happy dog and a happy family. It's likely that, with the right attention, your new pup has the potential to be a wonderful addition to the family.