I use Plastic SCM because its GUI is way more intuitive than any other alternative. Its merge engine allows me to stop worrying about conflicts coming from other people and the built-in semantic capabilities are just a delight. On top of that, the Branch Explorer is definitely something that improves my productivity every day, showing me a lot on information in an intuitive way.
I use Plastic SCM because I can handle, via Gluon, non-text or non-code assets in the same repo as the programmers I work with, regardless of the size, if I have to lock those or files or anything. It is a point and click interface that keeps version control for me in the background will keeping me away from all its complexities. It's the perfect #VersionControlSystem to do distributed or centralized version control when you don't like any of those.
Plastic SCM is built using .NET, C# and Mono. In Product we decided to go for Amplitude and Segment to track usage and monitor activation as well as Intercom to communicate news, updates and tips. The reasons to pick all of those are pretty similar: scalability and ease of use.