Heck of a way to start out the summer. Sorry to hear about the car.....glad to hear you are OK. Even sitting next to a Subaru at a light, you realize just how small we are compared to everything else out there. I am amazed that you are alright. Well done on your "Damage control" driving to the median.
When our 81 was damaged in transit (Transporter was rear ended), the first indications seemed to be that they would total the car. We gave them the body shop estimate and they sent out an appraiser that had no idea what to do. He said that they would likely get listings from Auto Trader for a value. Instead, we provided MWB's "cars for sale" web page and, (per Matt's suggestion),Haggerty's "value" web page as references to email to the insurance company representing the truck driver that hit the transport. They sent one big check and two additional supplemental checks when requested. Our perception is that your best chance for a decent outcome is that you have to take a very active part in the process. Otherwise, the other parties involved may just steam roller over you. Besides, half these people don't even know what an X1/9 is. You are probably more knowledgeable about these cars than some of the insurance appraisers as some have never even seen one. Best of luck & patience is on your side.