They appear to be a good idea for solo divers but I've seen a couple of these mirrors which have started to delaminate, if you're diving as a buddy pair or team they are not needed IMHO.
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Anyone know of any other 'versions' of this which might be more bungee friendly? Thinking it would be nicer on the computer or compass bungee.
Hopefully it's a bit convex as looking at a reflection in the watch or computer is too flat to be able to see the surface -- can use them to see bubbles; bit of a faff, but possible.