Im currently living in upstate NY and would like to move to boston or nyc?

Currently in rochester ny but i would really like to live in a city. My 2 options for work are boston or nyc. My immediate family is in NY but i have cousins in boston who love it. Which city is best for a 25 year old single guy? Also i would like to know the comparisons in living expences if at all possible. Thank you for your time and for helping me out.