question about sub-harmonic mixer

is anyone familar with sub-harmonic mixer, especially used in RFIC? what is the disadvantage of sub-harmonic mixer? for a direct conversion receiver , can sub-harmonic mixer help reduce the dc offset? if yes, what is the negative impact by using sub-harmonic mixer? thanks!

Pros

1. alleviate LO self-mixing (help DC offset to some extent)

2. resolve LO leakage to antenna problem

3. lower freq VCO and buffer could be realised at lower cost


Cons

1. high order harmonics and mixing products (out-of-band spurs)

2. some circuit architecture may result higher conversion loss (or lower conversion gain) and of course higher noise figure since the fundamental mixing product (RF-LO) may be higher than the expected output (RF-n*LO)