My experience is like that of @kstrauss and @popspipes.

I have had some problems, and Tormach has solved them promptly. For example, when my 770 first arrived, I realized that by a few inches, it wouldn't fit in the dumbwaiter that I have rigged between my carport and my shop. It would have fit if the a Y-drive component weren't sticking out the back, but I didn't know if that component could be removed without, say, unloading some vital mechanical preload, or losing some difficult-to-replicate alignment.. Or, it might be that removing the housing would give me only a fraction of an inch before some irreducible component filled the space.

I called Tormach and described the problem. The person I spoke to asked me to hold, then came back and told me that he had gone to a 770 there and opened up that housing. He told me what to expect there, what could easily be removed, how much clearance could thereby be gained (enough, it turns out), and what to watch for when I reassembled it.

That was in 2017, but lesser interactions since then have been almost as unqualifiedly successful. Like @kstrauss, I have occasionally made suggestions that appeared in the next PathPilot release.