I paid big money for the Dodge dealer to install a Jacobs on my '06 before it even left the lot. I custom ordered the truck, and wanted everything done right, and under warranty.
First pump went out at 35k miles. I had a trailer in tow, and was stranded on the side of the interstate. When the vacuum pump locked up, it shredded the serpentine belt, melted rubber in to the pulley grooves that took hours for a tech to remove, snapped the belt tensioner and sent it into the back of the radiator, and broke the fan shroud. It was almost a week of down time waiting on the truck, and I had to get a rental vehicle, and arrange for a third party to come pick up the trailer. I was late for my speaking engagement, and somewhat deflated, as I had planned to show off my new shiny truck to all my friends.
The second dealer installed Jacobs pump went out at ~ 72k miles. This time, it took out the bearings, as the shaft was wobbling considerably and sounded like rattling marbles. I bypassed the Jacobs pump with a OEM belt (not an easy job with a pinned Fluidampr

), and bought a Pac Brake.
I was happy with the retarding power of the Jacobs. I was not happy that the truck needed its 3rd vacuum pump already at 72k miles. Maybe I got two duds in a row. At any rate, I wasn't comfortable installing another Jacobs before heading out on a 10,000 mile trip to Alaska.
--Eric