I think this is a better way to enter drum notation (if you don't want Musescore to play it)

Start with a treble staff, change it to a drum staff. You can then put the notes in by just moving the mouse to the place where you want and click (like you would for say piano music) or use the other normal input methods.
You can get the different noteheads from the inspector.

So you don't have to keep coming back to the pesky drum palette, you can just add where you want, you can drag the notes up and down (very quickly) to where you want them.
If you want to change a note you don't have to delete it, go to the drum palette, select the note you want, go back to where you were and put it in. Or scroll through the entire drum map until you find the note you want. (I know you can change it with the letter shortcuts but not all the voices have letter shortcuts)

Only thing is Musescore won't play it as drum sounds but I never want that anyway.
Hope its a useful tip for others!