Use two.
Instinct for a personal assistant and either Grok Bot or Muse for work-related stuff. They all do essentially the same thing.
Grok Bot has the best interface, and looks/feels nice – but the usage is dreadful.
Muse has WAY more usage, like 20x Grok Bot each week, maybe more.
Instinct is the most like talking to a person, and is also free. It just works.