HTML:
Does that mean there might be (or is) excess vibration up the column with the 943
There might be...
All the oem steering shafts we make for anything with power steering (I think it's all power steering today) has an isolator of some type in it to prevent vibration/noise from transmitting up the column.
This is a very subjective thing... the automakers pay a lot of attention to the NVH (Noise, Vibration, Harshness) characteristics of a steering system... . the shaft being one part of that system.
It is also VERY subjective... one driver may not feel or hear anything, while another will be very sensitive to it.
All I'm saying is that if you are one of the more discerning drivers, you may feel vibration and hear the steering pump noise if you eliminate the rag coupling.
As far as durability goes, in my opinion the two types of shafts should be considered lifetime of the truck.
The wild card in how they will feel for responsiveness is the "flexibility" of the rag coupling... if its worn it may feel a little "softer" (will have a little more freeplay in rotation).
Hopefully that helps explain things a bit.
Maybe some of the guys who have put the 2 ujoint shaft can give us a heads up as far as what if anything they feel for NVH characteristics. These trucks are a bit harsh

anyway so maybe it's a moot point.
Jay