Generally speaking, Leapers = China. Some of the dirt cheap items from China are functional, I use Leapers scope rings with good results but refrain from other products particularly scopes due to their very low quality. The problem I see with the rear AR sight in question (at least IMO) is the clamping claw that directly attaches to the base. It appears to be made of sheet metal. From my experience, sheet metal claws are poor. Easy to torque down and bend them. Also, the nut the claw is clamped down with is the type that has the bolt going through the middle of the screw driver slot. On lower quality clamps that have this set-up, if the bolt is long enough, it will prevent the screw driver from going into the slot (as I've experienced in the past).
If the choice were up to me, I'd pass despite its price. But, it is cheap and should put you in the poor house if you are willing to try it out. (I've had more than my fair share of trying out low end stuff. Always looking for a great bargain. This sight does not look to be one of them.)