I think this is the one I have in the garage. https://www.airflofishing.com/polyleader-plus-trout.html I have had decent luck with it. I get the concept for guys that want a more durable leader...but I am not an advocate since I like to manipulate my leader as the situation dictates. The new ones, like this one, are pretty light, still heavier than a mono leader but cast fairly well. The one I have is designed exclusively for trout. I see the 'concept' for guys that cannot tie knots or don't want to learn. I will have to get it out now that we are in dry fly season and give it a shot since I have only thrown nymphs with it so far. I am not sure it is a concept that most of the anglers on this forum would adopt since I think most people know how to build out their leaders. But for those weekend warriors that grab a new leader every weekend and go toss a fly, it has a purpose and place in the market.I think floating poly leaders are the least useful variety of poly. I have a floater that I bought for fishing wakers for summer steelhead with a scandi head on a two hander. However, I think a mono leader does a better job, so the floating poly doesn't see much use.
I also have used a floating poly off a regular WF line while dry fly fishing for trout. They don't cast that nicely and hinge a lot with a standard WF line, they're heavy so they don't turn over very well, and they tend to land pretty heavily. If you're fishing big dries, like salmonflies, they're ok, but beyond that I'd never choose one over a mono leader.