There really isn't any difference as far as disposition, they are very similar. The main difference is in their coats. An F1 Goldendoodle has thicker hair than an F1 Labradoodle on the most part, not always but usually. With my experience, an F1 Labradoodle is much easier maintenance than an F1 Goldendoodle, again, there are exceptions. But, if you only have the one dog, the coat maintenance may not be an issue. I have not been around any F1B Goldendoodles, so I can't give my opinion on that. Both the Labradoodle and Goldendoodle have great temperaments (assuming they come from parents with good temperaments).