105mm polarizer wanted: cirular or linear?

Some linear polarizers will stump the focus and metering systems and cause issues since many modules have a plastic lens which might get influenced by the polarizer action (like looking at cellophane through one.).

Circular is generally favored for highly tech cameras over older film units or older rangefinders. Even some cheap "claimed to be circulars" have a linear characteristic to them and cause issues too.

Add, when you put one onto a slow lens (say f/4.5), it might have issues in general since around f/6.3 mine often will focus wrong with a CP or ND filter. Often I will shut off the AF with a CP on it.  Try manual and then switch on the AF and see if the lens spins off with the polarizer on it.

Mack