Hi,
I went to Wendy's for lunch just to try their Deluxe Fish Sandwich:

Compare it to the Filet O'Fish, it does not compete. The filet may have the illusion of larger because it is flatter, it is not as thick as the McD's, though there is the possibility they weigh roughly the same. Cheese is a 30 cent upcharge on a sandwich already more expensive than the Filet O'Fish.
While McD's now has a just-in-time delivery system with your Filet O-Fish is presumably assembled just as you order and boxed to keep it neat. The delivery of the Wendy's was about as quick as I uttered it from my mouth. While I try to take pictures as-is, it was really hard to make a somewhat flattened sandwich look better. The tartar sauce was applied to the lettuce on top of the fish filet, which made the filet seem drier than it had to be. This was remedied by getting extra sauce and applying it directly to the filet.
I ordered a combo, that had the option of several sides. I was quite happy with their chili, because the fish sandwich alone would have left me feeling much more disappointed with my meal.
While I will skip the fish sandwich, I might go for a bigger portion of the chili. This reminds of a chili cook-off story I heard over Christmas. One person's prize winning chili is based on buying a crockpot of Wendy's, then dressing it up with additional fixings. Nobody believes her when she readily admits to beginning with Wendy's as a base. They just believe she is withholding her recipe.
Regards,