I don't use either.
However, my 10-year-old AS son has a bottle (with a sippy lid) as his comfort object. He has not had anything in it since he was about 2, and he never even puts it into his mouth, but he has trouble sleeping without it. He CAN sleep without it if he goes to a friend's house, since he does know that even his friend with AS will tease him about it, but at home, he really wants it.
Usually when he is trying to fall asleep, he will hold his bottle up to his face and suck his thumb. Even without the bottle, he still sucks his thumb when he is trying to go to sleep. Even a palate expander and braces have not helped break the thumb habit.
The good things about this as a security object are 1) it is washable 2) we have more than one, and there is no preference between them and 3) if I had to, I could go to the store and easily get a new one.
Oh...and 4) It is reasonably small. My 7-year-old's comfort object is a big, square, floor pillow. And, he WON'T sleep without it.
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Mom of a 11-year old extrovert with autism. I also have a 9-year-old extrovert NT with ADHD. My husband is an introvert Aspie, and I am an extrovert Aspie. We are a strange family, but we all love each other.