LOL . . . gotta love this age-old debate since the dawn of CBS indicators. In short, the CBS interval is perfectly fine, and doing is more often than the CBS interval is also perfectly fine. There is no evidence that one is associated with greater (or less) engine longevity than the other.
However, there is a benefit to doing it more often. It makes those owners happy and feeling like they're doing something good. That's worth something.
