Pros
Culture, pay and workplace amenities are great. They are committed to the growth of their associates, and the company has a benevolent presence in its community. Associates are also encouraged to discuss hard topics (pay, representation, management decision making, etc.) freely. Finally, depending on your project, you will have access to some pretty cutting edge tech. Red Hat products underpin a large sloth of other enterprise technologies.
Cons
If I could nag for one thing it would be access to stock options earlier in the Red Hat career path. Aside from this, if you are a software developer, the usual pitfalls will still apply, i.e., work life can be hard to manage at times especially for remote workers, there is a political aspect to your work (what gets adopted, what doesn't and why) that you have to adapt to, and there are physical strains from stationary working over long periods. That considered, I am confident that Red Hat is one of the best places to work for techies.