@IndyFan - you have seen my UOAs with it. In the 3.6L, the average TBN is 2.59 after 5K miles. While there is a little life left, for me, it is not enough to warrant me going past 5K.
I would not consider RGT to be a long drain oil, but if one wanted to push it, one could likely get 7-8K out of it.