If you want a demonstration of what the 904 shifts like with Type F, think of Dexron as a wheeled office chair that is accelerated by a big bungee cord. Now instead of a bungee cord, have a filing cabinet full of bricks hit the back of the chair at 15mph. Thats Type F. Most chicks don't dig it.

There is less lubricity in the Type F fluid, but it will engage clutches better, making for less slippage, and heat.
The Synthetic Type F out there has similar lubricating properties to the Dexron, and still will result in firmer shifts. A benefit to performance applications, but decidedly not comfort.

Just how much accelerated wear type F causes, in my experience, is fairly minimal. I know people that have been daily driving with it for years, and launching down the strip on the weekends. On tear down, the issues have been unrelated to lubrication.

In a lock up converter transmission, Type F is a bad idea. Lock ups are prone to chattering, so very specific friction modifiers are needed. Lockup TC's have relatively small friction materials, so can't live in that environment long. There are modulating and variable lock up converters out there now days that would turn to slag in short order with anything but the latest formulations.

If your going to run Type F on the street, the best choice would be the Synthetic variants. That being said, I run Dinosaur type F with negligable wear in the Hooptie.
As Dan says, these are tough transmissions. I've smoked them with Dexron II and III all the same. The throttle valve setting is very important, as are the line pressure, band adjustments, and pack setup. We won't go into valve body and governer modifications, but they play a huge role in how the transmission will operate and survive under a variety of situations.

If the transmission isn't set up correctly; Line pressure, clutch pack tolerances, and so forth, it doesn't matter what fluid you put in there. It's just a matter of time. All the damage I've incurred have been the direct result of incorrect setup in one mode of operation or another.

We could blame my output shaft bushing clearance on Type F, but that bushing had 268k miles with an out of balance driveshaft before it wallowed out. Now that it's balanced, I haven't seen any indication of bushing wear.
Sure, type F doesn't provide as much lubrication. It still provides adequate lubrication for most parts. It also provides much quicker engagement, so isn't going to be the root cause of the problems likely to take out a torqueflite.

If your running an old unmodified transmission, run the latest Dexron. If you are building a fresh transmission and are meticulous about your setup, run whatever trips your trigger.
If you want a demonstration of what the 904 shifts like with Type F, think of Dexron as a wheeled office chair that is accelerated by a big bungee cord. Now instead of a bungee cord, have a filing cabinet full of bricks hit the back of the chair at 15mph. Thats Type F. Most chicks don't dig it.

2¢

CJ