Pros
ARM have their special culture, they put a lot of emphasis in taking care of their employees. Job content wise, they have strong ways of doing with a strong methodology team
Cons
The drawbacks of their advantage. Their dedication to the well-being of their employees may appear as political propaganda (e.g. is it the role of a Semiconductor company to hold a meeting about LGBT rights? - I just ask the question -, however the talkative communication of the company stops totally and unexpectedly when something wrong happens in the real life to the company like the issues faced by its Chinese branch) Also, they way of doing may be a little be detached to what it is done in the rest of the industry, they may be conservative in some ways (e.g. the way they use UVM). The way of working is so well and strongly implemented that it limits somehow creativity of the junior employees.