Mah IMO git is still pretty broke in 2013, hopefully they fix it for 2015. Lots of common features weren't there: cherry pick, rebase, gated checkins etc. You essentially could use the features you learn with git on day one but you have to throw away your continuous integration system to do it. We use git at my work but we use Jira/Stash for bug tracking/source control, and Jenkins for CI because we found TFS too broke under git and common things (admittedly not necessarily the best git work flow) like cherry picking from a release branch into the current dev branch required jumping over to git extensions/command line anyways.
If they fix Git support, or you can live with the legacy workflow TFS is again probably best in breed: nothing else integrates bug tracking, CI, and reporting so well. Web based solutions like Atlassian supplies just end up being a sea of links to other services you are paying for and you quickly run out of room for new tabs in your browser, FOSS tools I've dealt with each seem to fit a piece of the puzzle but need hours of massaging to get them to talk to each other. TFS: next, next, install, wait 10 minutes and you are 90% there and you get it with MSDN anyways so you might as well try it if you are a MS shop.