  Using only independent high-scale OPE input, we investigate QCD sum rule
constraints on two currently incompatible versions of the I=1 vector spectral
function, one obtained from electroproduction data, the other from hadronic tau
decay data. Sum rules involving weighted integrals over the spectral functions,
from threshold to a variable upper endpoint, s_0,are employed. It is shown that
both the normalization and slope with respect to s_0 of the EM spectral
integrals disagree with the corresponding OPE expectations, while both the
normalization and slope are in good agreement when hadronic tau decay data is
used instead. These results favor determinations of the leading order hadronic
vacuum polarization contribution to a_mu obtained using the tau decay data, and
hence Standard Model predictions for a_mu compatible with the current
experimental determination.
