This is a subject about which many people have very strong opinions, and many people have had very different experiences at all of the meals -- ranging from wonderful to terrible!
You'll find that sometimes there is a wave of threads detailing the bad experiences, and then another wave comes along where everything is positive. I think that any and all restaurants (character meals and otherwise) have good days and bad days.
My personal favorite is Goofy's Kitchen. I have a long, long history of eating there (going back to 1992), so even the days that have been 'not as great' in that time frame are not enough to turn me away. I have had enough good experiences there to outweigh any less than stellar experiences. I like the larger selection and variety of food at the GK buffet than at the other meals. Unlike the other character meal restaurants, Goofy's exists only to be a character meal -- in other words, whether you choose to do the breakfast/brunch (there is no character "lunch," per se, and the restaurant closes for a few hours in between brunch and dinner) or the dinner, there will always be characters. The other character meal restaurant locations have meals without characters as well.
I am not thrilled with the fact that Goofy's cut the number of characters down to 5, but 5 characters is pretty much what you will get at all of the meals except for Minnie & Friends. Minnie & Friends has the most characters -- everyone can agree on that.
Surf's Up with Mickey is the only meal with Mickey and Stitch, and you will see Daisy there as well. The character interaction is really good, and they are very attentive.
The Critter Breakfast at Storytellers Café is a more subdued, laid back character meal (quite a contrast to the high octane energy at Goofy's Kitchen), and the only one with Koda and Kenai. A lot of people like the food at this meal.
