Pros
The only pro I can think of now is that depending on the team you join you might work with some really exceptional people from the open source community.
Cons
Sadly, today's RedHat is nothing like when RedHat was an amazing place to work at in the past. Some teams are most likely still great to join, but I feel the numbers are dwindling as time goes on. As the various big impact event happened over the years, IBM buyout, CEO changes, recent layoff (more will surely come), whatever else, it slowly chipped away at the core spirit of the company. Nowadays it feels that a lot of new hires are getting hired to fill seats and to pad diversity numbers. A lot of really talented engineers are leaving in droves, the exception is the true believers who always wanted to work at RedHat and to them moving on to another company would feel like their world is collapsing. Loyalty is nice, but in today's tech world environment it is almost never reciprocated by the companies, so I hope they don't get disillusioned down the line by a sudden layoff. There are some others who carved out some niche position for themselves in the company, their manager is one of the few who is amazing to work with, but slowly they are getting replaced by corporate drones who sometimes don't even understand how to work with technology and they want to count lines of code as performance metrics. Teams are often put together randomly due to constant reorganizations, regardless of worker's capabilities of working well together or not. Then some managers who were driving these changes are surprised when personalities clash and work is not getting done as they envisioned it, because on paper it looked so good. Having said all that, I'm sure it's not any worse than most other organizations that grew really fast and then struggled with the consequences. I'm sure there are worse places to work for, but I would not be able to recommend this company to anybody I care about.