We've been for both and while there might be some slight differences, it was nothing we noticed. The signature items are there for both meals and in my opinion the best option for the F! Dining Experience.
We have been a few times, only 1 issue and that was a undercooked steak, they were great otherwise and even with the undercooked steak they made sure I was happy once it was fixed
We did the fantasmic lunch (picked a later time, 2pm) and the meal was fantastic, tons of food... filled us up enough that we didn't need dinner, we just had churros and popcorn while sitting waiting for Fantasmic instead. LOL!
We had the dinner this past June. I like the fact that you get an appetizer with the F! package even though we were on the Dining Plan and it wouldn't normally be included. Of course, it sucked that it thunder stormed all night and F! was canceled, but nothing we could do about that.
Went there back in 2008. Went there on my first day. Did Fantasmic for dinner and dinning plan. I remember my waiter went above and beyond. Dinning plan was to come with entree and desert. He added an appetizer on the house. I had chicken parm and remember it was really good. Going back either late Sept or early Oct this yr and going to get Fantasmic dinner package again. Keep in mind u get a lot of food so maybe that helps u choose lunch or dinner. Enjoy