For me they are both equal, and more than you will need. The supernova may be a bit better if you arenot too advanced. It will be just as good as catalyst, But catalyst is more for very advanced but it is not quite as stable. And I have 4 supernova and 2 catalyst so I know what these play like.
Spin time isn’t something you should really worry about with the metal yoyos available today. They’re all way, way more than adequate.
yeah spin time does not matter much most high end metals can do any trick.