I'm surprised a facade hasn't emerged yet. Personally I think it's nigh impossible to sanely do merges with a GUI. I know people do, but I think they're crazy. Using git via any JetBrains IDE is the best I've seen.
FWIW, I've only ever done git merges in a gui, and never had any difficulty with it.
It seems strange, but I really like having a console-based workflow with my VCS. I can leverage grep, shell aliases, and so on to customize my interface a fair deal, and the forced interaction helps keep me mindful of what I am doing.