  We study the stability of fuzzy S^2 x S^2 x S^2 backgrounds in three
different IIB type matrix models with respect to the change of the spins of
each S^2 at the two loop level. We find that S^2 x S^2 x S^2 background is
metastable and the effective action favors a single large S^2 in comparison to
the remaining S^2 x S^2 in the models with Myers term. On the other hand, we
find that a large S^2 x S^2 in comparison to the remaining S^2 is favored in
IIB matrix model itself. We further study the stability of fuzzy S^2 x S^2
background in detail in IIB matrix model with respect to the scale factors of
each S^2 as well. In this case, we find unstable directions which lower the
effective action away from the most symmetric fuzzy S^2 x S^2 background.
