Yikes, terrible 4 times? Isn't the old saying fool me once...
What exactly has been "terrible", because we have had great times here. We love the pools and the beach. I agree the restaurants are not great, standard rooms are just ok but we don't spend much time in them, and as far as "service" goes I guess we're pretty low maintenance, we check in and don't want to be bothered again.
I've not stayed at the Montage, but we've stayed at the Ritz Kapalua, Sheraton Maui, Kea Lani, Marriott Wailea and honestly we have the most fun at the GW. Fun. That's the word. Even without kids/grandkids we just loved the pools, and now with them the joy watching them have fun is irreplaceable.
We went to dinner once at the FS on Maui and I thought the pool area was just so congested.
Have you considered the Hotel Wailea? Adults only. Dinner was lovely there, I'm sure the rooms are great and the service is supposed to be unsurpassed.