Both of these sandwiches were extremely simple and were built using the same four elements, which made them easy to compare.
The buns were equally sweet and soft, and the creamy mayo complemented both flavor profiles well. Both fillets also had a flavorful sweetness to them that I appreciated.
Though I was able to detect a bit of additional flavor in the KFC mayo, it was a negligible difference.
Pickles are where these two sandwiches really differed in flavor. Popeyes used slightly thicker chips than KFC, and the tangy, acidic, briny goodness offered a welcome break from the richness of the mayo, butter, and greasy fry.
The pickles KFC used seemed to lack that same flavor. They were simply salty and acidic, and I almost wish they were left off the sandwich. Adding more acidity to the sauce could have made up for the absence of pickles.