I've just been looking at this stuff online and it's pretty impressive with a 20kg breaking strain (40lb) on the 0.28mm line. I currently use Shimano Technium Surf for spinning 0.30mm which has a breaking strain of 21lb/10kg so the Nanofil would be twice as strong for an almost similar diameter. I almost bought some but there are two bad reviews on Amazon that say the abrasion resistance is poor and it can snap after a few casts so I think I'll stick with the Shimano line for now. I used the Technium Surf line all last summer and only lost a couple of big fish on it which I think may have been them biting through the line rather than snapping it (big pollack).