Good points Cliff.
Early on I wanted to have all the Monk and Mingus possible. I've got a large portion of what's available, official and unofficial from these two artists, and I'm still learning from the recordings, definitely still enjoying them.
I'll confess that this is in a large part a "collecting" thing, but I very much enjoy the listening. The collecting part has a diminishing control on my time and money, thank goodness, but it's still strong.