I'm not a "Florida" guy, so not really familiar with Florida environments, but which is worse, rot and termites or rust and corrrosion?
In the North steel sheds have interior condensate issues and, thus, require a lot of ventilation to keep stuff inside from rusting. Wood seems more forgiving.
The floor loading will be an issue with tools such as lathes, etc. Check out how the floor in each is built, supported, and reinforced. You may need to reinforce the floor regardless of it being steel or wood.
Its a lot easier to wire and insulate a wood shed than a steel shed.
Pre-fab wood sheds can ususally be ordered in siding colors and roof colors to match your existing house/garage. Not so with steel sheds.
Easier to add some small amount of overhead storage or a high-shelf to wood sheds.
Get as big a prefab shed as you can afford. No shed or garage is EVER big enough!!