How you guys fish with Vanish is beyond me.
The same has been said of Fireline, while most Bass guys around here hate the stuff the Crappie, Walleye and some Catfish people love it.
I like it, a lot, for
some situations, such as Carolina, Texas and limited Flipping/Pitching fishing. And often with topwaters that are fished at distance, such as with a Zara Spook. It makes it more difficult to work a Spook, true, but I love the lack of stretch when the bait is way out there.
But not for cranking, spinner baits or a number of other baits/methods.
I am a strong believer in using a line type where applicable, IMHO no line type will do everything equally.
If you were around when I was a kid learning how to fish you'd be amazed at how far fishing line has come from the "good ole days".