Without a doubt Voyager balloons are at the top when it comes to experienced pilots. And that's what you really need. They have a good reputation as they have long standing experienced pilots.
My experience was fantastic and our pilot was so good he made me feel comfortable by making jokes and easing the situation when he could. Most of the time ofcourse he was very alert to surroundings and his colleagues on the ground.
Fantastic experience and well worth every penny.