We've used Fairy Godmothers a half-dozen times, and will continue to use them. The first time our son was about a year old. He's now 4 1/2, and we'll continue to use them even though he's old enough for the clubs, because he needs a good night's sleep after a busy day at WDW, not more running around in a kids' club.
My DS is language delayed and not that verbal, but I can tell if he's stressed. Even when he had stranger anxiety, he always loved the FG sitters, because they come with toys!
If you do searches, you'll find very few that didn't have good experiences with Kids Nite Out or Fairy Godmothers. And even those that did not like the sitters didn't feel there kids weren't being cared for...it was more like a personality conflict with the sitter.