So it doesn't sound like they have any problems. That being said, if you just got them, take them to a vet just to be sure everything is okay :) i got my glider when he was 5 years old and he never was brought out of his cage or given toys, so he is very skittish when out of his cage and will only stay on me. He never plays with toys. It may just be their personality, but definitely be careful because if they decide to be bold one day, they may leave you and go exploring.
Also, be careful with how many mealies you give. They are high in fat.
It's nice that they bonded to you so quickly :) My boy took about 6 months