I use git daily. It is an extremely versatile tool, I've even used it for deployment, and with enough hook scripting you don't even need external CI. Ask me about abusing bare repos. Stash is garbage.
hg is okay, its just slow as balls.
I recently helped everyone at work switch over to git as well, from various centralized VCSs. Even Microsoft has dropped their horrible Team Foundation Server crap and now hosts their own implementation of github inside their SaaS developer tools product. It's all cancer, but at least I can interact with it through git now.
>>8I wouldn't say I truly understand how git works internally
There are probably three people who fully understand the internals. I trust the people behind the software in any case.