I just added 112 sats to https://nostrbounties.com/b/naddr1qq9rzd3exuerzvps8qeqygplwuxkt5a8vj5utj6s8tsj8e3wcavc45p4mqmw92qs7wrh5azmyspsgqqqw4rstzzwfe! I have used hello talk voice room and it was a very good experience.  Good for language and cultural exchange.  The part I don't like is that there is too much emphasis on allowing users to top up and compete.