I was already well aware of the difference from exposure to competitive cycling. I just couldn't justify a second set of wheels till recently. I'll agree, it's a combination of wheels AND tires that made such a remarkable/noticable difference to me.
You could argue the point about where the $$$ could be better spent, But the improvement in so many categories of the cars performance was satisfying enough for me.
Now I'm plotting how to get a set of ceramic rotors.