I love that you can track your shipment in real time from start-to-finish! It's easy for customers/suppliers to see when shipments have been received or where they're at along their journey.
The only thing i dislike would be if there were more options available for tracking once it reaches its destination (i wish we could get an email notification). We've used this service before with other carriers like DHL but was never able to keep up with our shipping needs since everything had to go through them first. This has helped us cut down significantly on turnaround times especially during peak seasons which allows us to ship out orders faster than ever before!