When implementing react-redux for the first time I was a bit puzzled on whether to use the new hooks or existing connect API. The react-redux library documentation at the time of writing this does not seem to be strongly suggesting one method over the other.
I thought that there must be a downside to using the hooks since it's not being promoted as the new way to use react-redux. React.memo and useSelector seemed to provides all of the same benefits of the connect method.
My theory was if a component's props don't change but the redux stores data does the component would not re-render. It turns out that the useSelector hook does have a way of forcing re-renders of the component where the hook is used. I found this out by digging through the source code here. The re-rendering functionality is mentioned in the documentation for useSelector.
Mark Erikson has some thoughts on the tradeoffs when using hooks vs connect for separation of concerns. Using hooks couples your components to the redux store by direct usage of dispatch and useSelector.
While the connect method abstracts selecting state and dispatch through mapStateToProps and mapDispatchToProps by transforming state and dispatch into something more specific for each component. Which may make unit testing the component itself easier.
I haven't written tests for a component using connect just yet and I will have to write a few more components using both hooks and connect before I can come to any more conclusions.