  It is shown that the characteristics of the mesoscopic fluctuations in the
conventional quantum-diffusion model and the model of the non-coherent
(`classical') diffusion in media with long-range correlated disorder are quite
similar in the weak-disorder limit. The relative values of the variance and of
the high-order moments of the fluctuations in one model are obtained from those
in another one by substituting a proper weak-disorder parameter. As behaviour
of the ensemble-averaged diffusion coefficient is quite different in these
models, it suggests that the mesoscopic properties, including a possible
universality in the distribution functions, could be independent of the
behaviour of the averaged quantities.
