I took two online video training courses by Inspection 4 Industry LLC; API 510 Training Course and API 570 Training Course.
Bob Rasooli has prepared videos in which he describes all main and important aspects of related standards and exams in the best possible way. He explains everything in detail and covers all subject of the API 510 and API 570 exams.
Undoubtedly Bob Rasooli is one of the best in teaching and preparation training for API exams. In addition to videos, each course consists of numerous questions and examples which helped me a lot to pass both of my exams.
I highly recommend these training courses.