Hey cruzbound and gustele,
While I technically cannot say that I've used Bas Harts Diving, that is solely because I have not returned to Curacao since Bas Harts has been operating an independent company. I have both been on guided dives throughout Curacao and taken certification courses with Bas and I guarantee that you will not find a better time diving on the island. Bas is incredibly willing to customize an experience according to your diving interests and pursuits and he knows the island better than anyone I've encountered. He's an amazing photographer (just check out his Facebook page) and can serve as a personal guide, photographer, instructor, dive counselor, etc, all at once for you/your diving group. Apart from time spent under the water, I can think of nobody in Curacao I'd rather sit around with between dives to hear his stories and enjoy his company. I have little doubt that in a few years, he'll be one of the most well-known sources of dive guidance/instruction in Curacao -- so book him fast!
I give Bas Harts Diving my absolutely highest recommendation and welcome anyone to personally message me through ScubaBoard in order for me to answer any further questions that I can.
- John