DM, how can you say that you killed a 500 lb. bear with the .243 in one sentence, and then say it's not good enough for large deer in the next?
I'm not a bear hunter, so I don't know for sure, but I had a friend that killed a couple of large blackies and he said they were tough kills even with a 7MM mag.
I do think that the .243/6MM's are excellent for whitetails though!