We have a pair of Simpson Cooney davits on our boat
which were installed by the PO (or were part of the original build). Ugly b&astards they are, but they certainly do the job. We leave our 100+ kilo dink plus 54 kilo outboard on them in all weather
, including Force 10 gales. They don't flex or budge in the least.
I would be nervous about connecting davits to your mast. You will introduce forces and stresses into your standing rigging
which it was not designed to carry. I would think that at the very least, it will bend your mast back and screw up your sail trim. Besides that, you will add a good bit of windage aloft.
I would upgrade my davits, if I were you, rather than that.