I preferred the setup of the dive deck on the Black Manta to the Mermaid II, more room and fewer steps after gearing up. Two years ago, the Mermaid II crew clearly preferred entry and recovery off the zodiac boats; last year the Black Manta, used the zodiacs only occasionally. The cabins on the Mermaid II were marginally more comfortable but it was close and the Mermaid II has a seperate dining room. On the other hand, the lounge on the Black Manta was a much more comfortable place to crash between dives. Close, but if I do the Similans again, would probably choose the Black Manta.