I posted this on another thread re: the same question: We just returned from Poly Con GV, first week in June. You will not save money doing this. We did have breakfast here only 4 out of 7 mornings. We had 2 character breakfasts & room service once. The brkfst is nice, they have trays to take it back to your room. We never replaced dinner, and only went there twice during the service. We did enjoy dessert & coffee everynight (except one). And took water before heading to the parks. The other perks we received were breakfast PS at CRT, EASY check-out (the bellman arrived in 10 min, the bill was already closed out, and our car was waiting for us). We also had our room request met. The location of the building is wonderful too, by the pool, and both monorails.
If you can afford it, it is very nice. But actually, I don't think we will do it again, just too much $. We did it this time b/c with the discount code our package went down $200 when I upgraded to concierge. (if I hadn't upgrade, package would have gone down $800) Next time I'll take the money!
Have a wonderful vacation!!