I used to use the stuff. The last bottle that I had got dropped and shattered - apparently the solvent in the product had made the plastic brittle. That's been a while.
It's okay as polish and also contains some wax... and possibly a solvent that makes plastic brittle.
Novus2 does a fine job as polish and is usually less than $5 from whoever you're ordering a box of pin parts anyway.
The can of good ol' Johnson Wax that I got at least 10 years ago is still 2/3 full. It doesn't take a lot. Folks used to put the stuff on wood floors and walk on it.. (and slide around in socks!) It works. It's almost all wax.
Opinion of Millwax: No, thanks. I'll pass.