Which Subsee diopter to start with +5 or +10

I have never done any super macro underwater. I was wondering which Subsee to start with? A +5 or +10? I am leaning towards a +5.

I would be using this with a Canon 100L and full frame.

Thanks

The +10 is heavy on the end of your port and relatively difficult to use. However, it does give greater magnification and a successful shot will be more spectacular. Starting with the +5 is probably correct.