I have a DS4 with ASD(HF)/SPD. I do not know how he will react in WDW. He could be great with everything and act like an NT 4YO or he could not. I'm mostly concerned with catastrophic meltdowns and temper tantrums while waiting, but I would think that any parent of a 4 year old would be concerned with this. He is sensitive to loud noises, and certain smells, he also has pretty high anxiety, which can become worse the longer we wait. We're going at the end of September, so I'm not expecting large crowds/lines, would a DAS even be necessary?