Am I the only cat owner who fed my two girls whichever was cheapest at the time between Whiskas, Felix and Go-cat? They lived to 17 and 19 and never had any tummy problems. However Becky (the boss) was able to open the fridge and grab anything tasty inside. She once ate a cream cake!
I reckon that cats are a lot more fussy than dogs so whatever gets them to eat and still be healthy must be the best option. Try everything but stick to it for a few days to see if they are genuinely fussy or just being awkward!