Pros
The people are great. Everyone I work with is friendly and helpful! As a software developer, the work is interesting and challenging. The roles that are less customer-facing (like software developers and quality managers) still get to interact with customers during immersion trips out to customer sites where we get to observe real people using the software and talk to them about what is and isn't working. I didn't really appreciate it until I went on my first immersion trip but after having been on one, I think that all software shops should consider incorporating immersion trips into their developers' jobs. The campus is beautiful and there is definitely a benefit to being able to talk a quick walk around to reset or give your mind a break. The food at the Verona headquarters is delicious and affordable. Epic is fairly well known, so if you ever need to leave Epic for one reason or another, you will still be very employable. Epic is a very large company with most of its staff in Verona, WI so if you don't like the team you are on, it's possible to request a team transfer (though obviously it's not guaranteed that a transfer will happen).
Cons
Internal documentation isn't always the most up to date or easy to find. If you want to regularly work from home, this is not the place for you. As mentioned in the Pros section, Epic is a very large company. As much as the leadership would like a consistent experience throughout the company, Epic is a company made up of people, and people are different from each other. Some people mesh well and others don't, regardless of how good of a people they are. The quality of one's experience at Epic (and likely any company) will be heavily influenced by one's Team Lead and to a lesser extent one's coworkers. This is great if you have a great TL and coworkers (as I do), but can be problematic if you get placed under or alongside people who you don't mesh with as well. People on LinkedIn see that you work at Epic and flood you with requests regardless of whether you specify that you aren't looking for job opportunities. Seriously, if you get a job at Epic, consider deactivating your LinkedIn account.