Hi @AmyPeters, thanks for your question.
One advantage of using a custom field for this free text is that you will be able to easily use the Advanced Search to target specific text. That may be handy for you over time.
For example, in Advanced Search, Add a filter for “Add Custom Field,” select your text custom field, and then you’ll have options like the following (in my example, the custom text field is called “Subtitle”).
As a reference, here are the current limits for custom fields: I’ve reached the custom field limit: any ideas?