I have a 2013 F350 dually pulling a 36' Bighorn with a GVW of 14k.
Starting my 4th year of fulltiming and have had the MorRyde pinbox since day one. It works great and is SIMPLE. Seems to really knock down the chucking. The rubber donut that surrounds the metal pin absorbs the back and forth motion.
I also have a Hensley air hitch which eliminates lots (most ?) of the up and down motion that can be transferred from trailer to truck or from truck to trailer. Between the two of them I have a very nice ride.
I am a believer that it's smart to try and eliminate as much going-down-the-road wear and tear as is reasonably possible on both the trailer and the truck. My trailer came with 4 shocks which is a good start I think.