While the adhesive lined heat shrink would protect the connection from moisture, the connection is nowhere near as good. A proper marine crimp connector is made of tinned solid copper while the lower quality are usually aluminum. See Mainesail's site below for examples of the quality differences.
All About Marine Wire Termination Photo Gallery by Maine Sailing at pbase.com
Thanks Brian, makes sense. Marine connectors it will be this weekend then!
Is there an online source for these where they cost less than about $0.90 per unit?