The Custom Post Type UI (CPT UI) plugin is praised for its reliability, ease of use, and time-saving capabilities, especially for developers who need to frequently create and manage custom post types (CPTs) and custom taxonomies. The plugin's user-friendly interface helps users avoid writing PHP code, and it offers the convenience of exporting configurations as code which can then be added to themes or custom plugins. It works seamlessly with the Gutenberg editor and has fast, helpful support. However, some users note that it lacks certain advanced features provided by plugins like Advanced Custom Fields (ACF) and has issues with performance and support etiquette. Additionally, some find it lacking in documentation and some specific CPT options, while others experience frustrations with the extended version's pricing and subscription management. Overall, despite these drawbacks, it remains a highly recommended tool for most users.