  Within the framework of the relativistic distorted wave impulse approximation
(DWIA), we investigate the sensitivity of complete sets of polarization
transfer observables for exclusive proton knockout from the 3s$_{1/2}$,
2d$_{3/2}$ and 2d$_{5/2}$ states in $^{208}$Pb, at an incident laboratory
kinetic energy of 202 MeV, and for coincident coplanar scattering angles
($28.0^{\circ}$, $-54.6^{\circ}$), to different distorting optical potentials,
finite-range (FR) versus zero-range (ZR) approximations to the DWIA, as well as
medium-modified meson-nucleon coupling constants and meson masses. Results are
also compared to the nonrelativistic DWIA predictions based on the
Schr\"{o}dinger equation.
