I saw great reviews for this tool and purchased one hoping it would make tire changes easier. I have changed a bunch of tires with spoon style levers, and it's not that hard if you get the bead in the drop center of the rim. But tool claimed to make things easier so...
I tried this tool for the first time over the weekend and was very unhappy.
Before starting, I watched several videos of the tool being used and read the directions carefully.
But when I tried it, the tool badly cut the bead of the tire when putting it on the rim. This happened with a relatively stiff tire, a Pirelli Scorpion XCMH. It happened right at the beginning of the installation, when putting the first "bottom" bead over the rim. At this point, perhaps the tool is being used "inside out", as the sharp edge of the tool tore the rubber. But the directions clearly describe it being used this way.
I had to discard the tire and purchase a replacement, which I installed the old way with spoons.
I do not trust this tool and will never use it again.
You can see the sharp blade on the bottom edge of the tool:
And here are the cuts it made in the tire:
This is the approximate position the tool was in when it cut the bead. When I was actually doing this the wheel was under the tire and I was pushing the bottom of the tire over the rim.
Here is a pic from underneath with the tool in the position where it cut the tire. I think it is impossible to have that sharp edge on the tool avoid the tire in this position. The sharp "lip" on the tool is very shallow, and it is going to be right against the rubber.
Obviously many people think this tool is great. Maybe they are using softer tires or just have a better technique than I do. But it ruined a brand new Pirelli for me, and I won't be using it again. Spoons aren't that hard to use, and you need them to remove the tire anyway!