Mark was my PADI staff who I trained with when I did my PADI IDC in 2007, his dive & course knowledge is first class, his training techniques are excellent and is humour is top notch.  IDCs are tough and you need a Course Director who can inject a bit of fun in to the course at the right time. If you decide to GoPro with Mark, you will be in safe hands, learn loads and have bags of confidence going in to your PADI Instructor Exam.