AD9361 MDS, Sensitivity, and EVM

How do I determine the MDS and sensitivity of the AD9361 and in general a receiver based on a non-ideal IQ demodulator?  For instance sensitivity S=-174 +NF +10log(BW) + S/N of detector to meet BER.  But this assumes an ideal IQ demodulator.  So if my receiver requires a detector SNR of 5 to meet my BER with an ideal IQ demodulator, how do I now determine the sensitivity if I factor in an 17.8 % EVM (SNR of 15)?  And if I use a digital quadrature error correction algorithm (QMC) can I recapture or come close to achieving the sensitivity of the receiver with an ideal IQ demodulator?