When I first started dreaming about my dream garage, I got a quote from a SIPs manufacturer.
They are cost competitive with stick build, and the advantage is speed. You can get SIPs panels for the roof as well, which means you can be dried in very quickly--to me, that alone made the whole idea attractive. We priced SIPs for our Habitat builds--and may still do it, if we can find any property we can afford for our next project.
I thought for garage construction it was an especially good idea, since it would be easy enough to run all wiring in conduit on the surface, and not worry about using the wire chases that are usually put into the panels. From what I have seem, most use some kind of spline system for attaching, along with construction adhesive.
I have never seen anything like a SIP at Home Depot though, although it is not a bad idea. I'm not sure that their typical customer would be capable of building with them and meeting code.
