I used Mercurial with a hg-git plugin back in the day as we were a Mac-only shop and I was the only schlub with a Windows machine (I was in charge of fixing IE issues). Mercurial was very good back then, when Git performance was subpar on Windows.

Git on Windows is now blazing fast enough that msysgit will get you by. I still favor the Git workflow even when I am using other SCMs (like right now, where we have a Subversion dependency)