  The space-time reduced model of large N QCD with two adjoint Wilson fermions
is constructed by applying the symmetric twist boundary conditions with
non-vanishing flux $k$. For large but finite $N=L^2$, the model should behave
as the large N version of the ordinary lattice gauge model on a $V=L^4$
space-time volume. We perform a comparison of the $N$ dependence of several
quantities in this model and in the $k$=0 model (corresponding to periodic
boundary conditions). Although the Z$^4$(N) symmetry seems unbroken in all
cases, the N-dependence analysis favours the use of the same values of $k$ and
$L$ for which the symmetry is also unbroken in the pure gauge case. In
particular, the $k=0$ model, studied recently by several authors, shows a large
and irregular dependence on $N$ within our region of parameters. This makes
this reduced model very impractical for extracting physical information about
the large N lattice theory. On the contrary, the model for $N=289=17^2$ and
large enough $k$ gives consistent results, even for extended observables as
Wilson loops $W(R,T)$ up to $R,T$=8, matching the expected behaviour for the
lattice model with a $17^4$ space-time volume.
