Just replied (though they moderate replies) about both the 'guilt-free' aspect and that sushi does not equal fish bits:
The killing of an animal only for the profit of humans who have chosen to kill and the convenience of those who choose to pay them to kill cannot be considered "guilt-free" simply because a species is "sustainable". There are plenty of vegetarian recipes for sushi (a word which refers to the preparation of the rice only) that have nothing to do with the death of any animal, and yet your article on "guilt-free sushi" doesn't mention a single alternative to killing.
"A man can live and be healthy without killing animals for food; therefore, if he eats meat, he participates in taking animal life merely for the sake of his appetite. And to act so is immoral." ~ Leo Tolstoy