I also have not had a bad meal at Rainforest Cafe, and I've enjoyed it for breakfast, lunch and dinner.....BUT, much like brocklesnar69, I also have not eaten there since 2008. That's 3 years that have passed since my last RFC meal. A lot can change in 3 years - maybe the chefs at the DTD RFC are different, maybe the ingredients they use now are cheaper, maybe the service is worse, etc. Who knows? I do know that I have been reading many, many more bad reviews of RFC than ever before. So I am not counting my last 2008 RFC meal as being too helpful in advising someone to eat there today because too much time has passed since then.
If the RFC of today were the same as the one I ate at a bunch of times in the past, I would have a hard time picking between RFC and Storytellers because I like them both for different reasons.
But since it sounds as if RFC has gone progressively downhill, I guess I would say eat at Storytellers.
I personally don't think the dinner buffet at Storytellers (if it is a night when it is being offered - it's not 365 days a year) is worth it because there are so few choices. I only think buffets are worthwhile if they have lots of variety.
I would agree with DangerMouse and say to instead order off the menu at Storytellers. While Rainforest Cafe has many more choices on their menu than Storytellers does, Storytellers is a Disney-exclusive restaurant (RFC is not), it has a nice, cozy atmosphere, and what I have eaten there for lunch or dinner has been good. I am especially fond of the delicious spaghetti with meat sauce (full of fresh herbs) and garlic bread - I ate that dish twice on my December DLR trip. That stuff is heaven on a plate!