OK just upgraded from 6.6.7 to 6.7.0, had the marvell issue, as 2 drives failed to load up, and array couldn't start. Using card Vantec UGT-ST644R, which come to find out apparently uses a Marvell chipset (HyperDuo is a Technology Created by Marvell that Encompasses Both SSD and HDD Technologies to give You the Speed Without the Premium Price).
Anyways, since I also had another 2 port card from a previous build (upgraded old BM85 MB to a Supermicro X10SRi-F), added that card and now all is well again.