Ranked in these QuestionsQuestion Ranking
Pro Integrated compositing manager
XFWM has an integrated compositing manager, though it does have screen tearing.
Pro Left-half/Right-half window snapping
XFWM has a built-in option for window snapping.
Con Composite manager has screen tearing
The included composite manager in XFWM has screen tearing.
It should be mentioned that there's a workaround though:
compton --backend xrender --vsync opengl