Pros
Janssen is part of the Johnson & Johnson family of companies. J&J is a fabulous company to work for. They truly care about their employees and value their work and contributions. Compensation is much higher than my previous job at another Pharma company. They offer up to 17 weeks of paid time off for maternity leave. Health/retirement benefits are competitive with other big Pharma companies. As a company they embrace helping employees succeed in their careers and helping them move into positions/promotions that meet their career goals.
Cons
I personally haven't found anything I don't like about the company yet. I have been there almost a year. I think for the most part, if you are a good worker, it will pay off to you, and if you are not, you won't have the same opportunities.