Im pretty sure these were the factory originals 62K miles and 16 yrs, If I have to replace them again in a few years, Ill go with the new ones. I was getting a serious leak from the middle tube on the left side and a moderate one on the front tubes on both sides. Now to just see what happens. All in all, it was a simple thing to do with a Phillips head and 8mm wrench.
When I could see the stains around one or two of mine, I also replaced
the vacuum caps on the back and the vacuum line to #6... that's three
things I changed at the same time. One or all three contributed to a
noticeably better running bike

-Mike