Large Minyan or Small

In general, praying with a large group of Jews is preferable to praying with a small group.
Reason A large group is considered to be more honoring of God (b'rov am hadrat melech).
Note You may pray with a smaller minyan if you are not happy with the large minyan, such as the speed of the service, people talking during the service, or inconvenient timing when you need to get to work.