Hopcar knows his stuff.
I bought a 600' reel of 5/8" three strand off of ebay to use for permanent dock lines.
It isn't bad line. It is not as good as Sampson or NE Rope. However, for my purposes, it works great. My permanent dock lines don't wear from stress, they wear from chaffing. I don't live in an area where there are hurricanes so don't get the huge stresses that some do. However, my boat has been through a couple wind storms with this with no issues. We will see how it goes over the winter.
Anyway, at $283 for 600' it is about 1/2 the cost of NE Rope and in my use I seriously doubt the NE Rope would last twice as long. FWIW, I'd be happy using this line for an anchor rode as well. I may end up doing that when I get a spare anchor.