My DS7 is 2E--GT/Asperger's--as well, though in somewhat different ways from your son, so it's not hard for me to read myself into your situation.
I suspect that your son would have as many (or more)friends in the GT school as in the Cozy school, just because GT kids are likely to be accepting of him as a GT kid with eccentricities, and the AS kids at the other school all have their own social...difficulties...by nature.
I think I would prefer for my son, in this situation, to go where he could build on what makes him GT rather than a place where it was all about being AS. His elementary school right now does a lot of both, and while I understand his need for the social skills training and I'm grateful for everything they do in that regard, I would be hard-pressed to keep him there if they were not also doing well for him with the GT needs. It sounds to me like your GT school is not unfamiliar with AS, and they sound willing to work with that.
You may also be underestimating the brainpower that goes into the way that he says he solved the math problems so quickly. A less able mind would slog through the mathematics without ever thinking about the tricks.
The travel logistics might be the worst of your dilemma, but you might be able to find a way to get around those. Certainly I would go with him through the route several times to get it down, but mightn't there be some way to help that out? Maybe he would do well with a map, or written instructions step by step, or a GPS of some sort? Possibly a recording in real time, if the travel steps were reliable enough for that, walking him through each thing as he goes.
I hope you can work out what is best for you guys!
