Pros
I'm a recent hire who joined within this calendar year. This review is from my perspective as an experienced hire in a high profile group within ARM . My experience here so far has been very positive. This began during the interview process. I had a great rapport with my interviewers, all of whom were in senior roles to mine, and who are all now my colleagues. My first set of responsibilities set me up to demonstrate my strongest skills, which worked in my favor because I was able to be very productive from the outset, and delivered significant results within my first three months. This has in turn elevated me to further responsibilities. The onboarding process here was quite nice, with the Big Picture, and subsequently an opportunity to visit colleagues at Cambridge HQ whom I'd worked with. I've found the work stimulating, and the workplace environment a friendly and enjoyable place to be. Pay is quite competitive, and in my own experience, the range data on Glassdoor is disconnected from reality. The company is small enough that at least at this level, you feel that your role is significant, rather than being another cog in the machine.
Cons
The company is small but growing fast. Some things can be a little disorganized. A little patience goes a long way, because they really do try to fix things quickly, and there's no malice intended. It's nice to see that feedback for improvement doesn't disappear into a black hole.