I've used 2 international transporters, and I was very happy with both.
I sent a gelding to Saudi Arabia using EZ2SPOT out of Texas. They travel with every horse. There were a lot of paperwork issues on Saudi's side, but all were smoothed out by the transporter. My buyer was pleased with the condition when he arrived.
My filly is going to England Via Shortview stables. I've met them in person, and was very happy with them.
Both are in Texas.