I’ve tried GitSavvy and struggled using it.
I like Sublime Merge.
Install with Command Palette (Ctrl Shift P), Install, Sublimemerge 3.
Then use via Command Palette. E.g. blame > Sublime Merge: Blame File will launch a new window showing tons of detail.
Also, if you’re wanting Blame integration, take a look at Blame Explorer. Once installed just hover over the line number in a file to see the change log.