I was very impressed with this lecture series from R.C. Sproul to protestants on Catholicism. Overall, he presented the Catholic Church fairly and accurately. He highlights important issues and distinctions between Catholicism and Reformed Protestantism and does so charitably. One error (a common one among protestants) was the insistence in claiming that we "re-crucify" Christ as the Mass. It's not a re-sacrifice, but a re-presentation of the once-and-for-all sacrifice across time and geography. This is an important distinction.

A bigger theological quandary is one that he did bring up in that how can the human flesh of Jesus be present throughout the world (semi-omnipresence) without deifying the human nature of Christ, or otherwise blending and confusing the two natures? This, to my knowledge, is not a question that's been resolved or even studied much. ( )