I had two rounds of interviews. One a general one with the operations head and another with a couple of application scientists. For the second interview, I had to prepare a short presentation that focused on how to increase implementation of their technology. It felt more marketing than science so I was a bit out of my wheelhouse. Most of my experience was good. Unfortunately, I never heard from them again after the second interview. I think if you ask someone to prepare a presentation, you should at least email them to say they're going with someone else.