Well in another thread, some people are mentioning they dive single SM... The world is wideMy guess is a Scubaboard poll would find no primarily single tank sidemount, unless for benign tropical vacation shore diving. Though AL80 + AL19 might do well there also.
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And why always make a distinction between "benign tropical vacation shore diving" and other diving?
All dives need to be planned and it doesn't matter where and from where it is as you can dive in any configuration depending to your objective. Do you mean, tank being the same, a single SM is not the same as a single BM? In places where people dive single BM a single SM is not possible? Confused.