We're in the midst of building a complex, high-performance SaaS product alongside its associated marketing website, and TailwindCSS has been a pivotal asset.
In my experience, it is one of the few tools with just the right combination of tools that allow for the use of utility classes while still streamlining some parts of the CSS using @apply to maintain consistency. Not only does it facilitate rapid prototyping, but TailwindCSS also makes it a breeze to develop UI components that are both aesthetic and performant.
For teams looking to build sophisticated web products without getting bogged down in custom CSS intricacies, I can't recommend TailwindCSS enough. It's a powerful toolkit that delivers on its promise of efficiency and elegance.