Why would you run a mono amp for your midbasses? That will fully and totally trash the front soundstage. Also consider the new HCCA series Class D amps are not able to play above 250 Hz and have the abysmal sound quality of a Class D design. It is also quite likely that those subs you are wanting to press into mid duty won't sound that good trying to play higher frequencies. You're better off with a purpose build midbass and you NEED a Class A/B amp on any speakers up front.