TOPcast should be renamed Pinball University. It was very informative for me when I was new to the hobby. The entire archive is available. Do not judge it by the first few episodes. After they figured out how to use the recording equipment and turned it into an interview show, it's was outstanding.

Silverball with Rob and Steve was also good, but no longer in production.

I find gameroom junkies the most engaging. Good chemistry between the guys.

The pinball podcast is good, but I have not kept up.

Spooky has great guests, but I don't care for the format. It's a little too unedited for me. The Stern Christmas special was a recent favorite of mine.

I have not listened to the others.