About 37K miles, and absolutely no regrets. Towed our 43' 5th Wheel TH this last week, about 19500 lbs, and it was great. Strongly recommend the Aisin over the manual. Yes, you can shift. So what?
Modern automatics offer so many advantages (including manual override on many) that the only thing a manual says anymore is "Look at me! I love doing things the hard way!".
In the case of the Ram, the Aisin will maximize your capabilities, meaning that your truck will do more work without any modifications. But Ram has the manual for people that really want it.
The 5th Wheel/Gooseneck Prep is worth it.
http://www.ramgunner.com/ram5thwheel.htm
