  We study the Minimal Supersymmetric Standard Model (MSSM) constrained by
unification assuming mSUGRA SUSY breaking. In particular this means that the
three gauge couplings are unified at a {\it per cent} level, third generation
yukawa couplings are unified at a $10 $% level, and at the unification scale
$M_U\approx 10^{16}$ the SUSY breaking masses of squarks and sleptons are
universal up to specific D-term contributions. At $M_U$ we also include
right-handed neutrinos that are decoupled at their three respective scales. In
a top-down global analysis we then find that there are two distinct best fits,
primarily distinguished by the masses of the non-Standard Model Higgs states,
and compute the predictions for flavour violating processes involving both
leptons and quarks. The fit with the light Higgs spectrum is especially
interesting with regards to the decay $B_s\to \mu^+\mu^-$. We note that the
latter results go beyond what is called minimal flavour violation in the MSSM.
