  We present a study of the flavor symmetry breaking in the pion spectrum for
various improved staggered fermion actions. To study the effects of link
fattening and tadpole improvement, we use three different variants of the p4
action - p4fat3, p4fat7, and p4fat7tad. These are compared to Asqtad and also
to naive staggered. To study the pattern of symmetry breaking, we measure all
15 meson masses in the 4-flavor staggered theory. The measurements are done on
a quenched gauge background, generated using a one-loop improved Symanzik
action with $\beta=10/g^2 = 7.40, 7.75,$ and 8.00, corresponding to lattice
spacings of approximately a = .31 fm., .21 fm., and .14 fm. We also study how
the lattice scale set by the $\rho$ mass on each of these ensembles compares to
one set by the static quark potential.
