well if F250XLT is the biggest E4OD fan, then I guess I'm #2 or #3.
I've been running a built E4OD with the old Baumann controller for the better part of a decade and I like it. Having said that, I do still have some gripes.
Reverse engagement is delayed by up to a second. This is due to having excess clearance in the reverse clutch pack. Had I known more about this problem when building the transmission, I could have fixed this but until it dies, I'll just live with it.
Reverse ratio is very tall. And this in my view is the only real weakness of the E4OD. Anyone running 4.10 gears probably won't have any issues, but a nutcase like me with 3.08s certainly can stall it rather easily when pushing a trailer backwards up a ramp. If you're not careful, this can overheat the transmission. Fortunately, I did fit a transfer case when I did the C6 -> E4OD swap, so low range eliminates that problem. I had 3.08s with the C6 as well, and it didn't seem to stall as badly under the same conditions.
A better control strategy for the clutch lockup would have been nice. Currently, it can only be controlled based on throttle position and road speed. It will also unlock when approaching a shift point. This is fine, but as soon as it unlocks, the truck loses speed and changes its mind on taking the next gear. So now its running with an open converter and no longer accelerating. I timed sequencer protocol could have fixed this but its only a problem on light acceleration. And again, this is with the old baumann setup, not the new one. I have no idea if the factory setup has the same problem.
I did have the opportunity to drive a ZF5 powerstroke once (1995 I think). It had plenty of grunt but I found the clutch to be fairly heavy. If you're used to that, then its no real issue but I wouldn't want to deal with that after a long day at work. The same setup with a single mass flywheel was better, but it groaned very loudly anywhere below 1500 RPM. And I often cruise my engine in that zone when unloaded.
My "Toy" vehicles are all stick shift, but if the ZF 5 were the only manual option, I would pick the E4OD every time.
In fact, I'm even starting to daydream about how to swap in one of those newer ford 6 speed autos. Had a chance to drive some late model superduties when I was in the oil patch and they were very nice. Full lockup is maintained from 2nd gear on up, even when shifting. My personal company vehicle at the time was a duramax/allison combo and it still unlocked every time the transmission needed to change gears.
I didn't like much about the 2012-2014 ford superduties that I drove. Harsh ride, crude interior, tinny doors and vague steering that was overboosted. But that 6 speed auto with double overdrive? That was nice.