  We upgrade the study of the physical reach of a Neutrino Factory in the Four
Family Neutrino Mixing scenario taking into account the latest LSND results
that points out how the 3+1 scheme cannot be completely ruled out within the
present experimental data (although the 2+2 scheme is still the preferred
choice when four neutrinos are considered). A detailed comparison of the
physical reach of the $\nu$-factory in the two schemes is given, with similar
results for the sensitivity to the mixing angles. Huge CP-violating effects can
be observed in both schemes with a near, O(10) Km, detector of O(10) Kton size
in the $\nu_\mu \to \nu_\tau$ channel. A smaller detector of 1 Kton size can
still observe very large effects in this channel.
