When comparing adapta-gtk-theme vs Moka, the Slant community recommends adapta-gtk-theme for most people. In the question“What are the best Gnome Shell themes?” adapta-gtk-theme is ranked 2nd while Moka is ranked 4th.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Real dark theme
Pro Follows the material design guidelines
Pro Easy installation on Ubuntu
sudo add-apt-repository ppa:tista/adapta
sudo apt-get update
sudo apt-get install adapta-gtk-theme
Pro Most complete theme
It styles every nook and cranny of the OS UI, even the ugly Java apps look beautiful using this theme.
Pro Ergonomic
Not only looks good, but really accelerates work on desktop.
Pro Several distro specific instruction to download
Moka offers suers easy to follow instructions to download including PPA's for Ubuntu based distros and Fedora specific instructions to install its repo.
Pro Wide support
Besides this Gnome Shell theme there are multiple GTK and icon themes that match, giving the user a wide variety of themes to mix and match that still look great together.
Cons
Con No Debian support (sudo apt-get install adapta-gtk-theme)
Con Pertamax
Con Does not work on older version of Gnome Shell
Moka does not work on Ubuntu 12.04 nor will it work on Debian Wheezy as they both use old version of Gnome Shell.