Been to Bonaire twice and used Wannadive both times. If we go back I am pretty sure we would use them again. The first time my wife maybe had less than 10 dives under her belt and hadn't dove in a while - she came up too fast from only a few feet but she freaked out. Bob talked to her, and calmed her down and helped with her descent, and weights, etc....
Each trip we took a guided tour with Wanna Dive. The first trip was a night time dive around the town pier. As far as the guides went they did a good job of keeping tabs on everyone which was impressive given the traffic under the pier at night.
The second trip we had one of the DMs take us out on their "house reef" to show us some sea horses.
They have tanks at four locations (Golden Reef Inn, Bari, WannaDive Hut, their location near Windsock, maybe more we didn't know about), that was convenient especially when we stayed at GRI the first trip.
We didn't do the boat dives so I can't comment on that.