Very fast process, it took 2 weeks from the first interview to the offer. Highly recommend applying here, my experience was positive in every aspect.
1st interview: HR call with general questions about motivation, availability, and some situational questions.
2nd interview: ~45 min call with one of their VPs to find out more about my related work experience and motivations, as well as to answer my questions about the role.
Between the 2nd and the 3rd interview, there is a case study to complete at home (a presentation to test analytical thinking).
3rd interview: 2-hour on-site interview, consisting of several parts. First, a 40-minute interview with the hiring manager and another VP, then a 40-minute call with two team members based in London, then a 15-minute case study presentation followed by a 15-minute Q&A.
Everyone I've met was very professional and friendly, it was a great experience interviewing at Revenue Management Solutions. The projects they work on seem very interesting and stimulating, I think it's a great company to be in if you are numbers-driven and like analytical subjects. I ended up declining the offer, but the reason had nothing to do with the company or the package they offered.