I like mercurial not because I am fan, but pragmatic and my team can work well with it. I still use it on daily basis. Indeed my team use hg-git and also git to work with GitHub for synchronizing some upstream repository of libraries we are using.

Also you bring a topic of BSD, I used it since 1993 along with Linux and still use both of them. These days I don't use Solaris and other Unix though.

In early years used various flavors of Unix like IRIX, AIX, HP-UX, Tru64 Unix and settled on BSD and Linux.