I've seen it used in the saltwater environment with real high pound test line (100 or 200) but not in freshwater. No matter what type line you have to use the right size crimp if you go too big the line can wiggle or bind in the edges of the crimp causing possible failure of the line. With something as soft as mono or fluro I'd be concerned about line integrity with the lighter lines. Best used with wire of various types and even there you have to choose carefully (e..g. not with copper etc.). With that said I have always used crimps with stainless wire of various tests with good luck.