We did the FP+. With it, there are two options - one to pre-order your food, and one to select a time but order upon arrival. We did the latter, b/c with the latex allergy it is really just easier to communicate with the chefs directly. They have a protocol, but it is infrequently used and we prefer to run through it with the chefs.
If I had routine (top 8 ) allergies, I would pre-order without hesitation, so long as I was able to note it (not sure if there is a spot. Although, milk is hard, as it can be hidden, so I guess I would be hesitant to pre-order without an ingredient list.