Another perspective, with similar comments. Basically, you can't have too many sources of information.
We have sailed the past two winters partly (or almost entirely!) in the Bahamas. and used three primary data sources for charts. Combined with the standard cruising guide books (Important additions!) we never felt lost. None of the sources were "best" all the time, but combining them, thinking a bit, and adding some risk management we did fine.
We unexpectedly ran aground only once, on a shifting sandbar in a channel that none of the charts had marked. The other times we bumped bottom we were feeling our way along and expected it based on what we saw on the charts.
We used the NV Chart paper chart books for planning, and cross checking the electronic data. We were very happy with them. Not detailed in all the out of the way places, but excellent overall coverage. Relatively inexpensive, and easy to get a full set of paper coverage for the islands. I am always happier with paper charts in hand.
The main chart plotter had the standard Navionics chip. We found them no worse (and no better) then they are anywhere else. Sometimes with obvious errors that rudimentary quality control on the data should have found. We would definitely recommend NOT using the "Sonar Depths" crowd-sourced soundings for navigation.
We also used iSailor on the iPad. As a navigation tool, I dislike the iPad intensely, but as a separate source of information iSailor was great. iSailor uses Transas chart data, on a subscription basis. It was consistently the most reliable and detailed, although not always perfect. Transas' primary customers are commercial ships, and in the past I have read that their coverage is meager in shallow or remote areas where shipping doesn't go. We did not find that to be at all true--at least in the Bahamas and the USA east coast.
Enjoy the islands!
Annapolis, MD, USA