The designed orientation doesn't fit into the primary eyepiece holder if using ETX-90 with a red-dot-finder.
Can only fit to the direct holder with a prism hence limiting the alt. angle and changed the focal point so you need at least 50mm extender to get par-focal with a 26mm eyepiece on the primary holder.
Normal laptop USB port might not provide enough power for DSI II and causes random crashes but works with a USB hub with hight power ports.
All and all, this is a nice product to have for introductory to deep sky imaging but you will need a lot supporting components to make it work fully.
Pros: Good price at this level. Reasonable imaging performance.
Cons: The mounting orientation doesn't fit onto the primary eyepiece holder on ETX-90. Need a high power USB port.
This review was written in the old system and had content requirements that are different than reviews written today.