I've used them for more than 10 years now as an agency partner shipping containers between US/CANADA markets over oceans (Panamax).
The only thing that sometimes causes problems or frustration it's their internal system which makes some processes slow when there isn't much traffic during certain hours but overall they're great! Their team always help us solving any problem we had even if its been months ago so thats something i really like about GISI!! Always reliable services no matter what time zone where working out side office location around all world wide. We use this business because at least 90% percent reliability rate while doing ocean freight shipments through Panamskippers container ship lines using sea waybill documents instead paper bills etc..