I was unhappy with the dive lights my wife and I used on our last vacation, and a search for something better turned up this thread.
I ordered one of the 26650 XM-L T6 lights MRTdiver detailed from a US fleabay seller here.
It shipped fast, came with a 18650 sleeve but no lanyard, quality is very good for the price and the four modes are well spaced.
I don’t currently have 26650’s to test with but with a fully charged 18650, my light draws 2.6a on high.
It has a tight and bright hotspot and also very nice spill, these should work much better on our next trip.
I will order another one and probably perform the mod detailed in this thread to get better thermal transfer.
Thanks to MRTdiver for posting his experience and links, anyone looking for a small bright XM-L dive light should give this one a look.