Should I select COBRA or standard HMO through the state of MA?

I have the option of COBRA with subsidy for my old group health plan (somewhat expensive for me now) or a standard Blue Cross HMO for free. The BCBS HMO only lasts ten months versus the 18 months COBRA lasts. This is in Machusetts. I can't really pay the subsizided premium, but I don't want to lose coverage sooner either. Thoughts?