I've stayed at all three of the resorts you ask about. Only two of the three were concierge, GF and Poly. The GF was 17 years ago and the Poly was just this past summer. The GF I paid for, the Poly I was upgraded from a MK view standard room at no extra charge. The GF (concierge), at that time, I felt was terrific. The extras I received were very plush and had great value, in my opinion and the staff was great as well. I don't know if it is the same today, as it was many years ago. The Poly, however, I did not care for. Perhaps my incident was isolated, but the room quality I felt was poor as compared to the standard room we had occupied at the Yacht Club the week before. Room looked a little run down, several light bulbs out, fridge not working, and a little dirty and stuffy overall. The staff was inattentive (with one or two exceptions) for the most part and when trying to resolve the problems we had we met with resistiance instead of an attitude of co-operation. I was disappointed overall, I had expected my stay at the Poly to be "over the top" so to speak as I booked it for the last half of my trip. Granted, we didn't pay for the concierge service, but I would have been very angry if I had, my cost for the room was still over $500 a night for a standard room! IMHO, I won't do concierge by choice again and if upgraded, I may try to decline the offer, I just don't see the value for my vacation. We made most of our reservations ourself and I was hardly ever at the resort to take part in the "snacks" (goldfish crackers and gummi-bears) offered. They serve the items at certain times, and I ran up from the volcano pool to get something to snack on, but I was 2 minutes late and the staff in the concierge lounge must have been punching a time clock because they wasted no time clearing the snack table, I barely was able to get hold of a tortilla chip before the bowl was removed from under my hand. I understand there are schedules to follow, but if your expecting deluxe service, that wasn't what I was expecting, at least basing it on how my GF experience was. They do offer some hot food items, but to me I don't see the value, or should I say the Deluxeness. Our family's next trip in summer 2008 we have reservations at the Contemporary, no concierge.
You could have a whole different experience, I was just sharing mine.