If you failed (because I am) to use Git bash all the time just to look cool and geeky, the following article will help you to add GitExtensions support. So you will be able  to call them right from your Git bash or posh-git.

So my daily usage looks like the following:

#will open diff dialog

git ex viewdiff

#will open commit dialog

git ex commit

#will open GitExtensions start page

git ex

UPDATE

You can use the following PowerShell script to do all the stuff for you:

DVCS, git, git-extensions, powershell