A doubly spatially-correlated multi-cluster scattering Rayleigh MIMO channel with rectangular scattering cluster matrices (under the assumption that the minimum dimension of these matrices is equal to the number of transmit and receive antennas) is considered in this letter. The moment generating function (MGF) of the information rate is derived in closed form, based on Meijer function determinants. The MGF knowledge allows one to evaluate both the ergodic information rate and the outage probability corresponding to a given target rate. Numerical examples are presented to validate the analytic results.