Bests & Worsts Reviews from Amazon

I was very excited about this product when I read about it. Unfortunately, I should also have read the reviews. It worked marginally well. My dog still yelped when going through a know and the blades I think are terrible. I went on the Knot Out website and I was confused as to why they offer an upgrade with steel blades. Does that mean the one I bought has what kind of blades? I can't find that information anywhere. Why were we not told there was an upgraded model. I would have tried that first!