I enjoyed their process. The first test is about understanding how things work in a physical sense. I'm an engineer by degree and did fine. You'll either do well, or you won't! Don't worry about preparing (you can't).After that its more interviews, a few similar tests, group exercises (good fun) and roleplay stuff. Seemed like a nice company, a bit laddish perhaps and definitely wanting you to conform to their way of doing things (basically TOC... read The Goal by Goldratt and impress them) but I'd have been happy there if I hadn't had a better offer elsewhere.