What is the planned usage for the vehicle when finished??? For a DD/ light-duty WW the AOD is a decent choice, it has a decent 1st gear for off road and the OD will allow you to drive home without killing your fuel economy. Except that is pretty much where the usefulness of the AOD is exhausted - An AOD in stock form is quite weak and the TV cable can be problematic with some setups.
AOD Downfalls - expensive upgrades needed to get the strength of a stock C4/C6 - MVB's are out there but they are pricey ($500-700) and none are reverse shift pattern. Since R and 1 at opposite ends of the earth(seemed that way at times) you can forget any quick R to D shifting. Don't loiter in 3rd either, being a converter lock-up gear it WILL stall the engine.
For the hardcore offroad vehicle the best bang for your buck is a built C4 - smallblock applications or built C6 - 429/460 applications. I personally would not recommend a C6 behind a SBF for offroad since the C6 requires about 50-60 HP just to get things moving. Both "C" transmissions can be upgraded without taking out a 2nd mortgage. Jay at Broader Performance in TX offers everything you'll need to upgrade either unit to handle the abuse of offroad, he also had builds very nice converters as well. There are also many options for MVB's for the 3spd auto - including reverse pattern, no engine braking, and engine braking in 1st.
As long as you keep a c4/c6 fluid temp down you should see many years of use/abuse. Don't forget the important role the rest of the drive train plays in prolonging the transmissions life, large tires and or high gear ratios will lead to excess heat and will kill ANY automatic trans no matter the brand or build level.
