I replaced one on my '01 HO/6spd due to faulty diagnosis at around 105k miles which I was mostly responsible for. It turned out the stumble off idle was caused by the Jacobs Exhaust Brake sticking closed momentarily. I bought the replacement Cummins rebuilt VP-44 from a Cummins dealer for about $1450 and when we realized the take-off was not bad sold it to a guy who needed one for about $750. The replacement pump is still in the truck at 350k miles. The OEM pump removed from my truck worked well for a long time but I lost track of the buyer so don't know if he is still using it. My '01 was and still is all original except for Bosch 275 hp MH injectors which were installed when the truck was only a few months old.
I have the opinion that the VP-44 pumps are not as bad as some believe. Many reported VP-44 failures are due to a failed lift/transfer pump that the owner was unaware of, due to use of dirty fuel and/or infrequent fuel filter replacement, or bad troubleshooting (the reason mine was replaced), and other causes I'm not familiar with.