have alook at http://www.marlowropes.com/public/pageManager.cfm?page_id=132 where you will be surprised at the versatility of the D12. As to creeping, actually creep is the wrong word, the fibres tighten upon themselves under load and thus lengthen once first used. I tend to make up an approximate length, tie it between two supports and then sit on it, you can then readjust the end ( splicing only takes afew minutes )to the correct length minus about 25mm on the stays. After a few days they settle down and don't really move much.

The only down side I think is that you really need to change every couple of years the forestay as the spinnaker seems to " fray " the rope a little but 3.5 mm is much stronger than wire so theres a bit of tolerance left.

The other thing I would recommend is that on the 3mm trapeze line the loadings are fairly light and consquently the slippery rope tends to " creep " through the splice as its not tightening hard enough on itself. I now insert the end of the line 3 times through itself rather than the 2 as marlow recommends and have'nt had any bother since. <img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />

As to increasing the drag by 2%, can you check that as my instinct would say .002 as that is a huge increase in drag