We describe how unbounded three--form fluxes can lead to families of $AdS_3 times S_7$ vacua, with constant dilaton profiles, in the $USp(32)$ model with brane supersymmetry breaking and in the $U(32)$ 0B model, if their (projective--)disk dilaton tadpoles are taken into account. We also describe how, in the $SO(16) times SO(16)$ heterotic model, if the torus vacuum energy $Lambda$ is taken into account, unbounded seven--form fluxes can support similar $AdS_7 times S_3$ vacua, while unbounded three--form fluxes, when combined with internal gauge fields, can support $AdS_3 times S_7$ vacua, which continue to be available even if $Lambda$ is neglected. In addition, special gauge field fluxes can support, in the $SO(16) times SO(16)$ heterotic model, a set of $AdS_{n}times S_{10-n}$ vacua, for all $n=2,..,8$. String loop and $alpha$ corrections appear under control when large form fluxes are allowed.
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