Pros
I've worked for Eleven for 6+ years and had an excellent experience. Several people on the leadership team and some of the project managers are former freelance writers, so they get what freelancers care about. The managers at Eleven are also really great about introducing incentives like word count bonuses, rush bonuses, and rate increases over time. Overall this is one of the best companies I've freelanced for and would highly recommend them.
Cons
As with any freelance gig, work can slow down sometimes and it isn't always clear when that will happen. As the team has grown, it's gotten a little harder to keep track of people, but the leadership team has also been trying to address that with monthly workshops and social Slack channels.