Mike,
Google on filter bandwidth and the majority of the results will come up as the -3 dB point. Not saying the -6 dB and -60 db points are not useful info, just that the -3dB point is the common reference.
One other point is that -60 dB is in the dirt for portions of the nanoVNA measurement range. Rune would have to extrapolate the -60 dB point in that range which lends itself to possible inaccurate assumptions of the filter's behavior.
Herb
