All of the JM Costeau outfit is snobby and stuffy. They are pleasant and professional, but really uptight because they are trying so, so hard to present themselves as an exclusive resort.
Go here to dive Namena if your other dive shop isn't going to Namena. Costeau seems to go to Namena more than anybody else (twice per week, maybe). They are considerably more expensive to dive with, but if they are your only option to get to Namena, absolutely do NOT miss Namena.
The meal option on the Namena trip isn't worth the F$30. You have to decide if you want to grab better food in town for F$8-12, or pay JM Costeau an extra $20 for the convenience of them bringing it for you.
Once done with the dive, don't even think about having a drink at the bar while waiting for you cab back to town. They have a full page of rules that you are asked to review before stepping into their bar. The place feels like a funeral. And the drinks are double anywhere else.
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