Good communication throughout, very professionnal on their side, and things go quickly in my experience. I've had an initial phone screening with their head of talent, promptly followed by a 1:1 "informal chat" in their offices with a principal consultant.
They are very focused on their work culture and like to talk about their values and how they work, which are quite different from a lot of agencies that size. It gives you (and them) an idea whether you would really fit in that environment. That differs from my other interviews experiences, and so my one advice if you get an interview there is to prepare for that, and not just focus on what you can bring in terms of skill. Don't just be confident: make sure you can show you're confident, and have a narrative behind your answers.
They gave me helpful feedback after the interview and despite having relevant skills and experience, they were thrown off by a lack of enthusiasm in my answers, perhaps being too open-ended, being visibly stressed, apparent unawareness of body language, and so on.
If you're generally stressed with interviews, shy, introverted or neurodivergent, I highly recommend practicing for that, as it might be different from other interview styles where the emphasis is put on your own skills, aspirations, and have more varied questions.
It seems like a great place to work and I'm bummed that small presentation details are what blocked me, so don't repeat that mistake!