Hi tom, if you mean a perimeter line type of deck line I like 5mm or 3/16 nylon braided of some sort, yes it gets loose when wet and tight when dry but I figure for something that is used rarely but can be unlaced for an evergency tow line it works, the other option is an expensive boat line version of spectra with a polypropelene cover, real strong but doesn't run easily through padeys or loops. Regular polypropylene doesn't hold a knot well even though it floats. For my deck rigging 1/4" is a little tight. On my mariner a 1/4" line can stretch from the recessed cleats in front of the coaming to the steel u-bolt at the bow and back for a sloppy and usefull deck line.

As far as rigging for paddle rescues the regular 1/4" inch is fine , I put the perimeter line through the same loops on the sides so that it holds a little more firmly that just bungie, I haven't found anything better than the "x" in a rectangle pattern.
> I am about ready to rig the deck of my expedition single. Does any one
> have a favorite rope for the deck lines? 1/4"dia? how should I rig
> the bungie behind the cockpit for paddle rescues? should I double
> 1/4" bungie on the sides or use a larger bungie and just run it
> single?

> thanks

> tom