Who should join: USTA 3.0 - 3.5 players who want to play tennis in town (mostly in Waikiki). Short-term memberships are FREE. Events are FREE. Just come with a positive attitude.
Note that tennis lessons will NOT be given. Also, meetups should be free of overly-competitive and overly-social people.
Finally, if you don't know your USTA rating, but did play on the high school tennis team, then should fit right in. Similarly, if you don't know your USTA rating, but now play tennis recreationally a few times a week, then you'll fit right in as well.