I thought the whole thing was a bit ridiculous. Both are strong and seem to be good quality. Go with whichever you feel fits your maintenance plan and driving style.
FYI...I am definitely not taking sides or really care to start a debate, but I will share something from my personal experience: Back in my industrial hydraulic days I spent a lot of time in the machine shop where we saw a lot of repairs come in with gaulded parts. From that, I learned that like metals, no matter what the hardness, tend to gauld to each other in a friction type environment under load(stainless on stainless being the worst). In the case of the Longfield, it appears that the grease film is the only barrier between the two metals. Though they are different hardness, they are both steel. It would seem to me that if they ever ran the slightest bit dry under load, they would quickly gauld. Most hydraulic manufacturers use teflon or PTFE "wearbands" when using like metals together say in a piston/cylinder application. The "other mfg" mentioned in the thread uses bronze on steel in his u-joint. This method is widely used in industrial bearing applications and is by no means revolutionary. When it came out it was the first application I had seen in a u-joint though. The bronze is designed to wear and will have to be replaced at some point. You can purchase pre-fabbed sintered bronze(oil impregnated) bushings at your local Motion Industries or Applied Industrial Technologies and do the same thing that Cpt America was doing. You could probably get the right size right off the shelf. Bunting is a popular manufacturer.
(disclaimer: I am not an engineer and do not know everything. The above is merely from observation.)
