What do you like best?
Hands down, the team rooms are the single best feature that VersionOne has to offer. The team rooms offer a place to see your team's (and only your teams) backlog, a storyboard for the current sprint, taskboard for the current sprint and a slew of other options. It also includes the mini-game 'Estimably' which helps teams estimate stories anonymously without an confusion as to what story we are actually estimating. Overall, it's a great feature and makes it really easy to dive in and get a quick birds eye of where the team stands.
What do you dislike?
Looking at the product backlog can be very confusing. VersionOne doesn't include (at least in my implementation) a marker of which Epic, or if you are in the team room, which project a story belongs too. We had to adjust the naming convention of the stories to include an acronym describing which feature epic and which functional epic the story comes from.
Additionally, VersionOne for whatever reason, renamed everything to do with Epics in their platform to "Portfolio Items." Which to anyone with a scrum background is generally pretty confusing. I'm not sure why they made the change and while at it's heart it's just a label change, it's annoying that the deviated from standard agile terminology.
Recommendations to others considering the product
There's a lot of great features within VersionOne that you won't find anywhere else. But what it makes up in innovative features, it falls down in that it's not quite as customization as some of other competitors on the market. VersionOne has a clear vision of how you should be using the product, and deviating from the vision is difficult to successfully implement.
There are some features of the application that were implemented without a clear goal in mind, such as the "Add an Inline Story." On the surface, it looks like a quick easy to add a story. But there aren't options to add in Epics or Sub-epics to keep track of where the story goes. Outside of the backlog, where the functionality exists, it's not clear what happened to the story and it's not easy to track down in your portfolio view.
Additionally, with all the innovative features comes an 'innovative' price tag. Many of the innovative features will probably be overkill for smaller, and there are more affordable options. For larger organizations, the transparency and planning across many teams and many products makes VersionOne a much more attractive option.
What business problems are you solving with the product? What benefits have you realized?
We are a large organization implementing agile development across multiple teams, in multiple locations/countries. VersionOne allows us to have greater transparency up and down the line -- from the the status of a portfolio of products, down to the status of a specific story in a given sprint. The reporting has allowed us to project well in advance on the health of the project and raise concerns to upper management much earlier than we would have been able to in the waterfall method.