There's a lot of truth to what that guy is saying. Like you Vito, I am also using expensive fluoro for leaders, but let me tell my take on this. I do a lot of shore fishing...but its mobile
shore fishing...I cover a lot of ground. I can't pack a ton of tackle along with me, so everything I carry is in a small tackle bag. There's no room for a bunch of spools of line, so in the bottom of the bag is one spool of 12lb. mono...my choice as the "one line that will work for anything in a pinch". Practically every time out, I will bust a fluoro leader, and have to replace it with that mono. If it happens in the middle of a hot bite, I NEVER notice the action falling off after changing to the mono. I'm still rigging up with the fluoro at home, but my "in the field" experiences make me wonder why I'm spending the extra money!