I don't know anything about the Tonxy machine but after more than a year using an Ender 3 pro doing commercial prototype work for my company I have just purchased a sapphire pro 2. For the last year the Ender has worked perfectly once I had learned how to use it ! but the sapphire is much more professional in design and construction and without the Acrylic case it only cost me £11 more than the Ender.Having there was quiet a lot of assembly to do with very sparse pictorial (Ikea like) instructions and when first completed it was dead on arrival and only functional after a faulty extruder stepper drive module was diagnosed and replaced! Despite that it is well worth the price