I am an owner of the Dso quad. In my own opinion, the device as it is right now is usable. It’s not the perfect device to have in place of a genuine DSO/CRO with regards to calibrations / offsets. But, if you’re of the tinkering kind, the advantage of having this DSO is you have a ready made ARM platform with code that is open sourced which you might like to tweak. Personally, I like the idea of playing with the code a bit when I am able and learn while doing that.