I change my rudder lines every season as part of checking out all the bits on the ski. Spectra/Dyneema is definitely the way to go and to date I have never seen or heard of anyone breaking them. I replaced the steel cables on my multi sport kayak after the steel swages failed under load and the spectra has teh edded benefit of being quiet i.e. no banging against the bulkheads when the go tight.
The easiest way I have found to change them is the cut the old line and insert the end into heat shrink tube and then stick the new line in the other end of the tube (about 3inches is enough) and then heat up the heat shrink tube with a hairdryer (flames melt the spectra). Once this has cooled, just pull the old line through and the new line follows. Total time about 5 minutes.
Another perfect day in paradise. A bit of sun, a bit of rain and it's not even lunch time.
