from what i gather, some of the direct replacement parts, such as CDR valves, EGR valves, tensioner pulleys and other small replacement stuff like that, SS Diesel is fine, but move into the performance and upgrades over OEM, then SS Diesel falters.
SS diesel's PMD relocator is horrible. Have you ever held a marshmallow over a fire? similar concept. PMD= marshmallow, engine= fire. when not moving, the heat coming off the engine cooks the poor PMD when it is installed as per SS Diesel design. By moving it to the bumper, as the PMDcable.com and Heath Diesel kits do, effectively move the marshmallow away from the fire, eliminating the issue of overheating the PMD all together.
It is a little more complicated than that, I still dont fully understand it, but that is the explanation I came up with to show how SS Diesel's engineering dept. is not nearly as smart as the engineering guys at PMD cable and Heath Diesel.
I personally run a relocation kit from PMD cable.com, and am looking at getting a heath for my other rig just to try it out. When I got the truck, i could barely stand to touch the PMD (was relocated to an aluminum bracket that was intake mounted) but after buying the PMD cable.com kit, I cant feel a temp difference between the air temp and the PMD cooler temp.
good luck on the truck, you have made it to the Holy grail of 6.5L forums, and a damn fine one for anything else diesel you may have lurking around!