How you use the camera, what type of shots (Macro/wide angle) you take will influence how long the battery lasts. 100 macro shots is one thing, 100 w/a is another. Video burns batteries. How long you have the viewscreen active, etc. all influences battery life.
Honestly, how hard is it to change a battery after a couple of dives? You're going to be having lunch anyways...I never push my strobe batteries past 2 dives anyway. A camera with an LED trigger would, as would a DSLR. A camera with a viewfinder will use a lot less juice than a viewscreen. Maybe the GX85 or new Oly EM1 mkII.
Thanks, I understand, thing is, my last two cameras I struggle to get two dives. According to reviews, the RX100-V is worse than both in battery life.
Changing a battery, in theory is easy, in practice, not always. The quick change last trip resulted in a flooded camera housing. My first since 1984. I would like to be able to go a full day without opening the housing and I would like to use the sTTL modes for my strobes which requires a lot of battery capacity. The V is a step up or several steps up from my S90, except for battery where it has been judged worse by several reviewers.

Money to burn and nothing available which is why I am rebuilding my Nauticam S90.
Of course with the vacuum pump there is that extra security I suppose, hmmmmmm. Maybe on the go battery changes are more practical with that feature.
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