My youngest stepson is autistic, very high on the scale. They tried the compression suit with him, it angered him. (He wouldn't even wear the weighted vest). Every kid is different, I know that a lot of kids benefit greatly from it, it helps them focus.
I think it depends on whether or not your child also has sensory issues along with the autism. There are obviously many levels of autism - some children with autism also have sensory issues - usually in the form of not liking loud noises, and/or being touched or touching certain things.
I had a child in one of my special ed classes who would only drink applesauce through a straw because he was uncomfortable with the way it felt on a spoon. While another child hated being held, and yet another loved to cuddle. All were diagnosed with austism. (These were 4yr olds)