Pros
The people were incredible. The marketing team were some of the best, most competent people I've ever had the pleasure of working with, and it's a real shame that Sumo didn't see their value and made the entire department redundant when restructuring. I also was able to meet a variety of people working in different studios working on different games. I like that Sumo allowed each studio to have its culture and values, allowing each to feel like its own independant studio, while having the support of the wider family.
Kontras
The senior management sadly talked a lot of talk, and when it came down to it finally walked away after tanking the company. Two lots of redundancies later, and a lot of wishy washy language, Sumo doesn't seem that reliable of a company anymore. I will add, the gaming industry in general is a scary place to work, it's just so unpredictable, But, comunication is always important, and cancelling multiple 'town halls' because you can't face your employees doesn't give the best image.