In reply to John Kelly:
My anecdotal and totally unscientific view of skinny singles, having used and worn out quite a lot of them from a variety of different brands in recent years is: ropes with a sheath content of 40% last substantial longer than ropes with a lower sheath content.
The two ropes I have that have lasted longest are a Petzl Volta (not Volta Guide) and a Stirling 9.2mm, which I forget the name of.
Stirling ropes are pricey, but they are well made and last well.
I also have a dry treated decathlon 8.9mm which is holding up well. It was £90 for a 50m, which is a total steal.
In use it seems as good/bad as any other rope.
Beal Jokers go soft, quick in my experience.