Jive-x simmers...could sizzle!
WHAT'S GREAT: It looks pretty good OOTB. It's not that hard to set up or learn to admin. Customer Service techs are good to work with (answer cases promptly and try to help you, not just with links to documentation). It has a good internal search feature. Has native features, but allows third-party add-ons (like gamification). Allows for some custom communications with members. Has an open API. Community for CMs is robust and the members are pretty helpful. In fact, they're part of what makes Jive-x a good option. You have a little bit of help.
WHAT COULD BE BETTER: SEO is not great. Page-level re-directs? Really? API is NOT intuitive. Widgets AND tiles? Please pick a direction and go or provide feature parity. Every add-on or integration seems expensive. For example, the ability to re-name the author of old content is $5,000? Permissions are a bit byzantine. That community for Jive CM's? Jivers could be more responsive there, rather than leaving it up to members to swap info.