I would strongly advise you to either get some good training upfront or use a small project ( and involve a power user of LDD) as your first C3D project. It has some good capabilities, but it is very different from LDD.
Don't count on a huge savings in time and effort right away.
Styles are very important - you will need to get them established and set up correctly ASAP to get the drawings looking as they should.
You may find yourself using LDD for some things, but most things from LDD are easy to import into C3D for use.