All I am saying is it is not clear how long these transmissions will last overall. First things first, I think we all need to forget about the "Lifetime" fluid idea as this will only shorten the life of the transmission of the fluid is not changed. As for the valve body wear, this likely would not have been influenced by fluid changes, this appears to be more of a material and design issue than an maintenance issue. But this being said, I would recommend, 50-70k mile fluid change intervals, unless the then engine is overheated and then I would recommend a fluid change when the engine is overheated as many times the trans fluid temperature is increased due to engine coolant temps going up and/or the trans cooler not getting enough coolant flowing past the trans cooler section.
The valve body life cycle seems to be a function of the total number of shifts and possibly the area of the country you live in and outside temperatures.
My valve body was done by 70k miles, but I live in the Washington, DC area and within the first mile if leaving my house the transmission has likely shifted 20+ times. My wife used the car for her daily driver for 5 years before the valve body went, but she was commuting downtown 5 days a week. Stop and go traffic, shift, shift, shift......
The transmission likely shifted over 1000 times each day she drove the car to work. A wild guess is the transmission likely shifted over 250k+ times in the 5 years she drove the car on a daily basis.
If the car is driven mainly highway miles, I would expect that the valve body does not make as many shifts and you would likely get more miles out of the trans before problems show up??
Short of sleeving the valve body with stainless steel sleeves, you are likely going to continue to have valve body wear, even on the reworked valve bodies where the spool valve bores are reamed oversize. I do not know enough about the replacement spool valves to understand if they wear the valve body bores less. I assume that maybe the shape and material of the oversized spool valves may be a bit easier on the the valve body bores?
I kind of view the world this way, my orignal valve body lasted my about 70k miles. Likely my reworked valve body will last about the same amount (hopefully longer), with the additional transmission wear and tear on the clutch discs. So I look at it from an economic gamble, do I put $700+ into my current transmission, do I sell the car at a loss, or do I just continue to drive the car as is.
Driving the car with the bad valve body is really not an option, so this leaves either repair the valve body or sell the car.
I figured if I could get 2-3 more good years out of the transmission for $700 it is likely worth it to me. I would prefer to get over 200k miles out of the repaired transmission, but realistically the car is already 10 years old, the valve body design was not great to begin with and what happens when my reworked valve body goes bad, is the transmission/car still worth keeping in on the road? Can a reworked valve body be reworked and reamed oversize a 2nd time?
Not sure the answers to many of these questions, but I do not want to give people the idea that once the valve body is repaired, they will never have any more transmission issues. The automatic transmission/transaxle is clearly the most single complicated assembly in any car or truck these days.
Lots of moving parts, electrical connections and components, software and many seals and gaskets. Just way too many areas for problems and failures and we should all be lucky enough that we get the life out of these transmissions that we do.
So I tend to be a bit more glass half empty kind of person when it comes to making statements and setting expectation on things I cannot control. I do not want to give anyone a false sense of what to expect.