I opted not to futz around and have ordered new hubs as well. If I was going to use the existing back-plate and just change out the shoes (longitudinal crack on the curb side shoes), I might have left them. But since I'm changing out the whole back-plate assembly, the new magnets wouldn't meet up properly with the surface. Checked and looks like it would be hard to find someone in my neck of the woods who would/could machine those surfaces, so... what's another $250 at this point