I want to change the button command to "Prefs SETDEFAULTLISTER=force,quiet", but I'd like to have the Default Toolbar Set saved also. Will that happen, or not?
I can't check from where I am, but you could test this easily for a definitive answer.
If you want to be sure, add the command to save the default toolbar set after it and it will definitely do it. The command is in the default Settings > Toolbars menu, if I remember correctly. (Not at a PC currently.)