is pulling arrows out of other parts of the target as easy as the core? And how often do you have to replace the core? Are pass throughs ever a problem?

It's pretty easy to pull from anywhere. There is a picture on this forum of a skunk that has over 4000 shots in it. The skunk is pretty small and if it is taken 4000 shots and doens't pass through, that should tell you how good they are.

The Rineharts are great targets. It is very easy to pull arrows and they heal up very well.