In reply to victorhearnyeates: personally I wouldn't bother unless you were going to wash your ropes anyway. it will give the rope SOME repellency but not enough to make me want to use it in winter, say!
In reply to victorhearnyeates:
I did a pair of ropes with this stuff, it was better than nothing and I have used them in winter but they wern't as good as proper dry treated ropes that my mates had.