Can I chant the ‘om namo bhagavate vasudevaya’ mantra?

From: Mukul Joshi

I’m chanting hare krishna mahamantra but sometimes i feel more attracted towards ‘om namoh bhagwate vasudevaye’! apart 16 rounds of hare krishna, can & shoould i chant extra rounds of ‘om namoh bhagwate vasudevaye’ or preferably ‘hare krishna mahamantra’ only.