  We solve $O(n,1)$ nonlinear vector model on Bethe lattice and show that it
exhibits a transition from ordered to disordered state for $0 \leq n < 1$. If
the replica limit $n\to 0$ is taken carefully, the model is shown to reduce to
the corresponding supersymmetric model. The latter was introduced by Zirnbauer
as a toy model for the Anderson localization transition. We argue thus that the
non-compact replica models describe correctly the Anderson transition features.
This should be contrasted to their failure in the case of the level correlation
problem.
