  We study high mobility, interacting GaAs bilayer hole systems exhibiting
counterflow superfluid transport at total filling factor $\nu=1$. As the
density of the two layers is reduced, making the bilayer more interacting, the
counterflow Hall resistivity ($\rho_{xy}$) decreases at a given temperature,
while the counterflow longitudinal resistivity ($\rho_{xx}$), which is much
larger than $\rho_{xy}$, hardly depends on density. On the other hand, a small
imbalance in the layer densities can result in significant changes in
$\rho_{xx}$ at $\nu=1$, while $\rho_{xy}$ remains vanishingly small. Our data
suggest that the finite $\rho_{xx}$ at $\nu=1$ is a result of mobile vortices
in the superfluid created by the ubiquitous disorder in this system.
