When I play armies with flying monstrous creatures I usually dedicate my two 125pt warrior/blaster/venom with extra cannon units to holding objectives in my zone while shooting at the FMC's. You can move 12" with them, snap fire with the passengers(you're shooting at BS1 anyways). results in at least one of them getting grounded each turn. Like Massaen wrote-"Once their down though, we own them." They really aren't that bad to deal with in my experience.
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