On first glance the build quality is great, but there are some issues:
- The mirror cell is an open one, so the mirror is not fixed in forward direction, so it shifts when the scope moves, and it is losing collimation all the time even during the imaging session.
- The secondary mirror is glued to the holder without too much precision, so when you align it, it is not centered, which is unfixable.
... I've tried all possible methods for collimation /many times/ and still the stars are far from perfect.