Not Very Good
This stem is quite cheap at about $40. It is a great stem if you plan on using it for transport (in association with a bike of course lol) and when you are not landing on the stem or anything of that nature.
The bars move, no matter how tight the stem bolts are. Grease, sanding the paint on the bars and even lock tight don't seem to solve the problem.
I would not recommend this stem to anyone other than people who solely want to use it for riding on the ground, no jumps or tricks. The handle bars move when I use this stem no matter what I do to help or how much I tighten it. At the end of the day moving bars is not what you want and money would be better invested in another stem.