Pros
From my experience to date, Cirium is a stable and flexible employer. As a child organisation of RELX(FTSE 100 entity), the company has a solid financial base for growth. Work/life balance is very good (hybrid and fulll remote available dependent on individual circumstances) and there are several intiatives to keep employees engaged individually and as part of the collective.
Cons
The pay is not the best; so perhaps, not the optimal place to be if you are a real tech talent and are looking for premium reward for your skills. Additionally, Cirium itself isn't so large and from my experience & observation so far, not so much scope for vertical promotions. Highly ambitious employees can perhaps look to advancement opportunities across the other companies in parent organisation, RELX.