I for one wouldn't mind purchasing a Higher Quality String in that price range if it lasted really long that still felt like new with great performance. I think the Body of the Yo-Yo's and the Bearings and Response have seen great strides in recent years. The strings, yes of course too BUT I still have to change the string after 8 hours of play on it. So give or take every 2-3 days, I have to use another string costing me .19c.
I haven't been able to know how lond this string last, but I hear that I can go for a month without breaking. I've been using mine frequently for a week and it still fells like I made it yesterday