As much as I take the subway almost daily, I wouldnt recommend it with 1 person and 3 bags of luggage.

Is it a weekday or weekend youre coming in on? That would make a difference due to the rush hours youll be travelling in if its a weekday.

Id say best option is take the $12 bus to Grand Central and than walk the rest of the way (or taxi 10 blocks if you need to).