If I were to draw up my datacenter in my notebook, VirtualBox would be my choice to be included. If, for example, I need to run Docker, I can do it inside VirtualBox. In my opinion, it's the best solution for a small office or one-person virtualization.
Room for Improvement
It has a few kinks here and there, and Oracle should definitely improve on those, but if you know how to use it and are careful with your use of it, then it works perfectly. For example, I have some objections regarding how it uses virtual memory. If you oversubscribe the virtual memory, it just kills your notebook.
Use of Solution
I've been using it for five years.
We've had no issues with deployment.
There were some small instability issues with version 5.0, but they seem to all be fixed now. It works perfectly.
We've had issues with scalability. This is something that Oracle should work on.
Customer Service and Technical Support
I don't know if Oracle even has support for VirtualBox.
The initial setup was straightforward.
We implemented it ourselves with our in-house team.
Other Solutions Considered
I tried VMware, but they kept asking for more money for upgrades again and again. I also had a Windows license, but not a Linux or Mac license, so I just decided to go with VirtualBox.