They'll last a lot longer with less maintenance if you do.

Laszlo

   Pretty frequent question, and Laszlo is right.

But, his boat stays out in the weather. If you plan to keep yours under a cover or in a garage don't bother. Varnish or paint will last plenty long and you'll save a few pounds aloft.

Cheers,

e

   Both answers are 100% correct.  Still, I vote for the epoxy now.  It is never easier to put on a good finish than now while the shop is set up, the spars are new and unrigged, etc..  If you save only one re-varnish over the life of the boat (and you'll likely have saved more than one) you'll have ultimately saved time, and meanwhile the spars will stay in better shape over the years. No (or many fewer) discolored spots from where they where the varnish was scratched or worn through while in use.  And I'd say certainly do the ceterboard and rudder, so why not spars while you are at it?