Adams Marimba Schlägel M12

My favorite line for four-mallet marimba playing is the Rober Van Sice series from Adams. Great for solo, ensemble or even orchestral playing as well.
Six hardnesses in both mono-tone and multi-tone, they have all the hardnesses that makes sense on Adams marimbas, so I would argue that you do not need any other mallets if you have these.
My personal though is that these mallets were made for Adams’ marimbas while other brands’ mallets were designed for other manufacturers’ instruments - that is why i think these will always sound better on Adams instruments.