Welcome to the forum. I could have almost helped you with this query, but I opted out .
Was going to buy a used 4x4 Stinger 2 , and after a lot of research I suspect their built like a tank .
My only beef is that huge enclosure mounted at the front, as thats probably where I’d like to stand on occasion.
Imo I wouldn’t be interested in the older models that only used one stepper for the Y axis . Although they say it was one fine having one stepper on one side of the gantry , later models incorporated 2.
The CAMaster forum was really friendly and helpful . I couldn’t get over how quickly they responded, so I think you’ll have a lot of support