[tang daddy]

It really depends what you're cutting,

Firstly if there is salt residue or liquid that penetrates the dremel it could corrode the internal parts.

Also I am not sure if these dremels have a diamond blade for cutting coral skeleton, I would imagine they do have one for doing small tile work and such.

Also you may need a jig or table cut out to rest the dremel on, I find using 2 hands to cut coral with a saw is easy but definitely can be done with one hand.

Just going by the pics of the product, haven't used one for coral, I have used dremel rotary for sawing larger coral objects but more for scoring then using coral snips to break. Need to do it in a plastic bag or coral juice which stinks lingers around the area.