The customer is using the PrimeFaces in some applications. Is there some advantage to use for example PrimeReact in some other applications in the future?
There are for example the Roma and Babylon themes in both PrimeFaces and PrimeReact libraries. Is it so that they look exactly same?
Is there some advantage to use for example PrimeReact in some other applications in the future?
I would say, make your choice, but I would not mix them and stick to your selected technology. There is a great answer on the related question: What is the need of JSF, when UI can be achieved with JavaScript libraries such as jQuery and AngularJS.
There are for example the Roma and Babylon themes in both PrimeFaces and PrimeReact libraries. Is it so that they look exactly same?
Themes on all current Prime libraries are based on PrimeOne. So basically they share the same CSS and will look the same. You can check for yourself:
I noticed they are very similar, but there are some spacing differences in the demos. The differences you are seeing are probably due the demo implementation and not due to differences in the themes.
