Chik-Fil-A isn't even close to being in the top ten fast food restaurant chains in the world or in the USA (it's the 21st largest in the USA and much smaller world-wide). But all you need to do to make a chicken sandwich taste good is use MSG as the third ingredient, after chicken and salt, as is the recipe for their sandwich.
As to the topic at hand, living in Austin, one of the self-proclaimed taco capitals of the country with tremendous options on nearly every block, I don't think that I'll be rushing to try BK's tacos, but I will admit to a secret and shameful love for Taco Bell every once in a while...