I have mounted a steel rail (L section) directly to the lower front edge two the lower two of my FATAR keyboards and connected them to the black plastic support by several screws, because I am planning to install 2nd touch to these keyboards somewhen in the future. For normal playing (with normal key pressure) the bending is not nice, but will not damage the FATAR keyboards, I assume. Mounting a supportive metallic rail, however, is not a big effort.
Regards,
Frank.