Why not both? you *shan't* be limited by anything other than the size of your HDD
One aspect is concern about having enough time to participate in both in satisfying ways.
Another is apprehension about being able to keep the twain sufficiently mentally separate to avoid making past-writings-referencing remarks in one place that presume past-writings-context of the other.
Not that I'm nearly as concerned *now* as when I initially posted about it. :-)