DAS doesn't own any of their carriers. All carriers are private contractors that transport scheduled pick-ups based upon a posting system - similar if you were hunting for a job or looking for a dorm room on campus. These carriers are nothing more than a scheduling business that acts as a 'shell' to a network of private owners. You have found out the hard way that using the same carrier doesn't guarantee the same level of service. Glad you at least got things sorted out without it taking tooo long or having to involve a 3rd party.
I have used DAS twice for two of the rides and another pair of carriers for two others. For the 5th car I imported I actually flew all the way down to Houston, and drove the car all the way back to Calgary. It was 2/3 the price of transporting including all my airfare, gas, food, and accomodations. Just needed to lose myself to 3 days of solid driving which was just fine for me as I was importing a nice little 2 seater convertible during the late summer. The drive was nice all in all.