Pros
This is not true for all groups, but where I worked: Small groups working on specialized projects can provide an innovative and fun environment. Due to complete absence of management oversight on a day to day basis, the right personality can apply many skills and gain internal satisfaction doing so. As my group became smaller (managers left to other groups), the working environment became more enjoyable. I know this is not often the case, and I felt very differently when my group was larger (where "souls go to die" is not untrue). I was satisfied with the benefits and compensation. ...Until upper management decided to incompletely dissolve a group and shut down a facility on a whim.
Cons
There are no formal reviews. No on-paper recognition for contributions of lower-level workers. I received regular raises and moderate, unspecific verbal praise through and past the day I was laid off (part of the large layoff in 2019). My departure left a significant deficit in skills that IPG has not replicated 1 year later. I am certain that no one besides my team and direct supervisor was aware what I contributed. I also think that an entire product line was scapegoated for issues that were 100% relevant to poor management. There were few well organized projects with milestones and structure. This would have helped contributions to be visible and added to my job satisfaction. Management utilizes the innovation of those below them, typically without giving credit, to advance their position to a level they are incompetent for. If you are an outgoing narcissist, you will do well here. Everyone else will end up stuck in their lab, if lucky, with like-minded good people. If you are unlucky, the lack of management means toxicity and incompetence are also unnoticed and can fester. There is a significant amount of sexism, cronyism, elitism, and bullying. The wastefulness due to incompetent planning and poor oversight is rather distasteful.