It’s an intriguing and, dare I say, rather particular inquiry.
The first portion of my response is more of a clarification of a point of confusion I had when I first read this. Because caviar is officially the salt-cured eggs of sturgeon or other members of the sturgeon family, it is always black or white in most places of the world (excluding the United States, as far as I can tell). However, after researching what you meant by red caviar, I discovered that in the United States, salmon roe and, less typically, roe from other salmon family members are referred to as’red caviar.’
In terms of my own choice, I would always choose the highest quality available, as well as the highest quality that you can afford. Sturgeon caviar is common, however it’s rather pricey in comparison to most forms of salmon roe. My issue with caviar stems from a debate I have with myself whenever I buy pricey ingredients: