I purchased some of that 8 strand from pyrosupplies and I wasn't very happy with it.  It appears bleached.  It could just be me, but I kept breaking strings at the nocking point.  I gave up on that spool after the third string, which was really overbuilt, broke at the nocking point.  Again, it could just be something I was not doing correctly.  Also, I found the breaking strength of that particular product to be less than advertised. Steve Gardner (badger) reported similar test results.  I don't have the numbers handy but it was more like 40-50 lbs breaking strength.  I am going to try to grow a crop this summer too.  looks easy to grow, but taking plant to bow string fiber sounds like a bit of an art.