  The differences between the oscillation frequencies and uncertainty estimates
of a star derived by different fitters can be large, sufficiently large so
that, were one to find a stellar model that fitted one frequency set
($\chi^2\sim 1$), it does not fit an alternative set. I give 21 examples,
comparing frequency sets in common between the Kepler Legacy project and
frequency sets from Appourchaux et al (2014) and Davies et al (2015). For
16CygA&B the differences are large; the $\chi^2$ of the fit of Legacy to
Davies's values ranging from 1.64 to 11.47 for 16CygA and 1.62 to 1.79 for
16CygB, depending on which error estimates are used. I analyse both stars in
some detail applying my own mode fitting code to both the Legacy and Davies's
power spectra and find reasonable agreement with Davies's full frequency sets
and very good agreement between values for modes with signal/noise > 1 ($\chi^2
= 0.06, \chi^2_B=0.03$). But the difference with the Legacy values remains
large even for modes with S/N>1. I also examine the effects of different power
spectra (weighted and unweighted) using the kasoc light curves for Q6-17.2 and
Q7-Q16, the effect of different mode height ratios and different rotational
splitting and inclination.
