My boyfriend and I were in Fiji in April this year and stayed in about 4 different spots all around Fiji, one of them being Oarsmans Bay. I did a lot of research on all the places and as we were on a budget as well so we stayed our first 4 nights at Oarsmans. The beach is absolutely lovely! The clearest water I've ever seen and the best snorkelling ever. And the boat trip to Nanuya which is about 10 mins away, is fantastic and the snorkelling there is even better. Had a fantastic time there however, there are numerous issues with the staff at Oarsmans. Most of the staff are nice but not as friendly as the other Fijians we encounted. Also we weren't able to have cocktails as they had no fruit juice and limited drinks as they had not ordered any. The food was usually okay, however you don't get any choice, which didn't really worry us but other people weren't happy with the food at all.
It is situated in the most beautiful place, and well worth the visit, probably not more than a few nights though. If you are a patient person and prepared to negotiated with the staff you should have a good time.
We had a lot of people leave Oarsmans Bay days early as they were unsatisfied and went to mantra or octopus. Both I heard we great.
Hope you have a good trip.