Talked with Colligo Marine people and they really don't know the life expectancy of the rigging. They feel safe quoting a six year life span but feel that it will last a lot longer. They have an ongoing testing program to try and get some real data on UV degradation, etc. When you are 4 times plus the required strength of the shroud, there is a whole lot of room for degradation of the material. Given that stainless wire and fittings are really suspect after 10 years in the tropics, a six year life span ain't so short. If you do the splices yourself, the costs are quite a bit less than SS wire and even cheaper for a rerig using the deadeyes and lanyards over again.
FWIW, someone on the East Coast rerigged a Westsail 32 with Dynex Dux. That was a couple of years ago. Would be interesting to see what his experience has been.