I think so that.......

A side mount is easy to use.
A side mount is convenient.
a side mount diver can cave dive without buying BC newly.

A side mount spreads a place to cave dive.
There is the passage of side mount only too.

A side mount diver kept his head high and be walking with chest out.
How do you think?
Japan caves information
Come to " the Asian Cave Exploration"

SideMount by Cavetek Club
"Cave diving in Japan"