Just an update. My family did do this excursion and wanted to share. @DocLC is correct - it is not very deep and I would have liked it to be deeper but it was good for 2 in our group which had never snorkeled before and liked that they could stand up when they needed to. Did see some different wildlife which was neat. My family really liked the seeing the Iguanas and petting them.
Was looking at the excursion offered by RC for snorkeling at Lobster City, seeing the Iguanas, and spending some time at Big French Key Beach Club. Does anyone know anything about this excursion? Is the snorkeling any good? How deep is it? I am not finding many reviews.