Group Poll: How many hours between mag overhauls?

Yes. My thinking is this. You have one older mag and one newer. You
also have one from one batch and one from another (or one rebuilt by
one guy and another rebuilt by the other guy). So your odds are less
that they will BOTH fail on the same flight, which is all you really
have to worry about (although one failing in IFR when needing to climb
could be a major concern, I suppose).

Once you have replaced one, then replace them in every other fashion,
always keeping an older one and a newer one.