FluentSMTP has garnered significant praise for its ease of setup, intuitive interface, and robust functionality. Users appreciate its ability to connect seamlessly to multiple email services, including Sendgrid, AWS, and Office365, without hidden costs or need for a "Pro" version, which differentiates it from other SMTP plugins. The logging feature, which tracks sent emails, is particularly appreciated, as is its capacity for integrating with various services and providing detailed documentation. However, some drawbacks include intermittent issues with configuration, particularly with Microsoft365, occasional failure to recognize email credentials, and incompatibility with PHP 8 and above. Despite these issues, it remains a highly recommended solution due to its free access and reliable performance.