Pros
Despite being highly apprehensive about whether to attend, my recruitment consultant ensured me that it would be an overall positive experience, and I'm very satisfied that I listened. I've been placed with a great company, and Celsius have overseen the entire process seamlessly, with regular catch-ups with my rec consultant. The day was well organised from start til finish. The Celsius staff did everything possible to make myself (and other candidates) feel at ease. The exercises, while challenging, was a good opportunity to "impress" the clients as they listen in on the group discussions. There is a classroom culture to the discussions, so you have to raise your hand to respond to a question. I believe that this ensures everyone is able to make a contribution. The recruitment consultants tend to get a good understanding of what role you'd be best suited to and work meticulously to get successful candidates placed at the right company for them. The MD gives a very useful workshop on interview skills in general - offering insight into what employers look for in candidates. There is no set number of candidates that they have to reject so they won't needlessly cut candidates if everyone is doing well.
Cons
I can only speak for my experience at the Assessment Day, and our group was quite small (15 graduates). My impression is that their high standards may be harder to deliver at some of the larger groups. *Only 2 candidates were cut in my group (I think they weren't always thorough in articulating their opinions, so I think it was fair. Back up your answers with logical reasoning and examples, exuding enthusiasm and confidence, and you can't go wrong!) The psychometric test was a bit confusing as some questions were repetitive so I felt I had to check back at previous answers to guarantee that I wasn't contradicting myself.