Yesterday I bought some 10lb Nanofil at Basspro in Nashville. I am not satisfied with the knot strength at all. I feel the knot strength is about 10 to 20 % of the rated lb test. I bought 10 lb and I have tied the Nanofil knot about 5 times and it broke very easily. I am using a 4/0 offset wormhook to tie the line to. I am wrapping the line to the spool around a piece of wood. I embed the hook point into another piece of wood. I pull with a slow steady pull until the line breaks. The nano knot didn't slip but the knot broke every time with very little pull on the line. I tied the grinner knot. same results but it did take a little more effort. Maybe 2 lbs of pressure. I did the old palomar know and it broke very easy. None of the knots slipped. For comparison I went to the barn and tried my old 10lb fireline. I did the palomar knot on the 4/0 worm hook and embedded the hook into the corner of my work bench. I wrapped the line from the spool around the block of wood and pulled. I had to pull hard and the worm hook was bending under the load. When the Fireline broke it broke at the block of wood. Not at the knot !!!! I will contact Berkley and let them know my results and I want a refund or exchange on the line. I do not recommend this line for anything.