[gadusmorhua]

I don't understand why 20lb Sufix 131 is no good for topwater lures, but 18lb 131 is- surely there's hardly any difference? Try a tiny bit of mucilin on your braid if sinking rate is an issue for you.
I've found 131 perfect for my very rough ground, I use 20lb and it still looks good after over a year's use. No wind knots and it behaves well for me.

 

[gadusmorhua]

First use was good but after that I soon noticed the colour fading and the breaking point reducing. Given most of my fishing is targeting species above line strength I buy, it simply wasn't acceptable.

Often you will find those stating they have not had any issues with it are using heavier line such as 20lb to target bass where even an exceptional specimen would be 10lb. Unlike the UK where a decent sized bass is far from common, here its almost guaranteed to catch fish after fish in the 4-8kg size from the shore. So testing any line or tackle soon finds faults, not to mention most of these species targeted are fast hard fighting pelagic's.

Unfortunately posting these facts on here soon turns people defensive on the line they have but the fact is that the fish are here in numbers so testing any part of a tackle setup can be done in a short period which could take a lifetime to do back home.

Agreed, UK bass will never truly test the 20lb braid I use, but you get to know the dud ones when you have to pull for a break, which is quite often on my marks. I'm happy with my 131, and don't want to keep trying other, equally expensive braids. Before you know it you've spent more than a top end rod.
Definitely worth buying a top quality braid though, cheaper in the long run and the performance is far superior.