Caution: Difficult to get aligned! I inadvertently mounted it at an angle the first time which lead to leaning prints but once I fixed it, it's been working great.
It IS very hard to get the belt tensioned (especially because the tension can vary between three different segments of the whole belt) and it is difficult to get the sliders level (one compared to the other). So my advice is to use an electronic level that can be zeroed. That way you mount the z-axis perpendicular to your XY plane, NOT the ground. Be patient. It really works well if its all squared up and straight.
Spools are a must on the top brackets.