I've seen less than 5 bad pumps in 5 years. At Honda, we'd do is automatically with the tbelt. Not that they'd leak, just more $$ for parts and labor. Some of the other dealers do it or sell it to the cust as an option. The 960 pumps go more frequently than the 850 one. Also, you risk gettin a bad pump or not getting a good seal on the gasket, and you're worse off than before. When people ask if it should be done, I tell them only if it's leaking. It's a can of worms not worth opening.