You may measure the benefits of infinite scrolling with the example of a Facebook news feed. By unspoken agreement, users are aware that they won’t get to see everything on the feed, because the content is updated too frequently. With infinite scrolling, Facebook is doing it’s best to expose as much information as possible to the users and they are scanning and consuming this flow of information.
The biggest usability problems for radio buttons come from labels that are vague, misleading, or describe options that are impossible for average users to understand. Contextual help can alleviate the latter problem, but it’s still best to user test any important set of interaction controls.