RoadRunner Auto Transport
RoadRunner is the clear #1 on this list. Their carrier network covers every major freight corridor in the country, which means cross-country loads get dispatched faster and rerouted more flexibly than at smaller brokers. Thirty years of operations gives them institutional knowledge of the long-haul routes that newer brokers are still figuring out. And their in-house operations team manages the load actively for the duration of the trip, not just at pickup and delivery.
For a coast-to-coast shipment where things can go sideways at any of a dozen points along the route, that active management is what separates a smooth shipment from a stressful one.