I would just buy yourself some scales and go the TouchDro route. Yuri is coming out with Version 3 any day now. Im ditching the MX200. If anyone wants to buy it let me know, I'm keeping the scales though, you can buy them separate.
The touch dro supports up to 4 axis and has a summing feature. I plan to add a 6" scale for my quill and sum that and the knee scale together, very cool feature IMO. My tablet was $79 on Amazon, Yuri's board with housing was $129. I bet you could find three magnetic scales for under $500 and have a much better system than them all.
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