Aod Or 4r70w? Which Is Better?

From what I've come to understand after rebuilding a couple the major flaws on the AoD boil down the the tiny 3/4 secondary input shaft, roller sprag, and the stupid band that engages the overdrive is easy to torch if you are beating on it all the way into OD. They have 1 piece input shafts for AoD but the 3/4 shaft is your converter lockup so 1 piece shaft = no lockup and lots more heat on the street, hardened input shaft would be way to go on a street car imo but as you feared even the hardened ones have a bad history once u put power to them. Roller sprag is easy fix they make a diode that is lots stronger. And the only good fix I have seen for the week OD band is don't do any (well many) flatfooted shifts into OD. I only have 400ish hp to mine so not taxing it a ton but its alot of fun with transgo shift kit, chirps em right into 3rd. If I had it to do over again I would probably go with a 4r70w build after seeing the weaknesses of the AOD but like I said I don't make enough power to brake mine since I upgraded it. Not even positive a 4r70w would be better have yet to mess with one, but sure looks better on paper.
 
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Well aside from all the bad things I heard about the heat from non-lockup converters does having no lockup on yours make the OD ratio different? My main deal was I do alot of interstate driving and figured constant slip at interstate speeds would = cooked even with an enormous cooler. Whats your experience with highway/interstate driving with the non-lockup?
 
Heat is usually never an i
Well aside from all the bad things I heard about the heat from non-lockup converters does having no lockup on yours make the OD ratio different? My main deal was I do alot of interstate driving and figured constant slip at interstate speeds would = cooked even with an enormous cooler. Whats your experience with highway/interstate driving with the non-lockup?

Heat has never been an issue for me. Snapping the input shaft when i left the OverDrive switched on and downshifted to 2nd and hammered the gas did once. (Snapped the 3/4 shaft)

With a good stacked plate cooler you should be able to run anything you want. Your first easiest and probably cheapest transmission MOD should be the largest stacked plate cooler you can fit behind the grill.
 
Get the 4R70W it has all of the upgraded goodies already that they put in the AOD's. It has the ratchet one-way clutch, upgraded direct drive drum, steel drums, better servo and bands sizing etc. and the ability to hold more clutches/steels. its a better foundation to add on in doing a build. I also used a non-lockup converter in my AOD as recommended by Hughes because the lock-ups cannot handle horsepower is what I was told. They also told me that they pretty much act like a lock-up since they are near lock-up 96-98% without the failure.
 
I'll definitely get the 4r70w now. I also was told that the non lock up was stronger, my worry has been highway driving though. I'm still a little confused when people say lock up can't take the power, do you mean in general at any time, any gear without it locked up or just when the convertor is locked up?