KWin is the main reason which I'm not using KDE Plasma Workspaces anymore. In my case (GeForce GT 630 with nVidia proprietary driver0, KWin results in a lot of tearing in games, videos and in its effects, it has a poor performance and it is very buggy. So, as compositing window manager, it's a bad solution for me. I prefer to use Mutter in Plasma Workspackes rather than KWin.
And this is list of the packges to install together with KWin in openSUSE (excluding the recommended packages).
appmenu-qt cln kactivities4 kde4-filesystem kde4-kgreeter-plugins kdebase4-runtime kdebase4-runtime-branding-openSUSE kdebase4-workspace
kdebase4-workspace-branding-openSUSE kdebase4-workspace-ksysguardd kdebase4-workspace-liboxygenstyle kdelibs4 kdelibs4-branding-openSUSE
kdelibs4-core kdepimlibs4 kscreen ksplashx-branding-openSUSE kwin libakonadi4 libakonadiprotocolinternals1 libattica0_4 libdbusmenu-qt2
libdmtx0 libepub0 libgps20 libkactivities6 libkde4 libkdecore4 libkdepimlibs4 libkscreen libkscreen1 libksuseinstall1 libphonon4
libpolkit-qt-1-1 libpoppler-qt4-4 libprison0 libqalculate5 libqca2 libqimageblitz4 libqjson0 libqt4-qt3support libsoprano4 libssh4
libstrigi0 libwayland-egl1 libxcb-composite0 libxcb-damage0 libxcb-image0 libxcb-keysyms1 libxcb-randr0 libxcb-shape0 libxcb-sync0
libxcb-xtest0 libzip2 nepomuk-core oxygen-icon-theme polkit-kde-agent-1 shared-desktop-ontologies soprano soprano-backend-redland