I've been using digital scales on my mill drill for many years and I haven't had any problems with them. The first thing I did after installing them was to run a wigglier up against a parallels mounted in the vise and after 5 runs I had 2 that showed a .0000 error and 3 that showed .0005 error, not very scientific but it proves they are good enough for an HSM, not pro's, who is going to be satisfied with a .001 accuracy. You can get a 3 axis read out for them (I got mine from CDCO, at the MAMES show, they seemed to have the best price at that time) that allows you to cover them so they are protected.