Pros

Greater tolerance of temperature variation.
Less requirement to buy and maintain clothing.
Greater safety and health, in and out, of water.

Cons

More care required to minimise sunburn.
Greater vulnerability to insects and prickles.

Pros

Joy.
A greater sense of body security.
Greater confidence and self esteem.
Enhanced ability to relax.
Enhanced social warmth.
Generally better working conditions.
Reduction of inappropriate feelings of lust.

Cons

Assumptions of disapproval by others.
Concern about discovery.