It's fast, it has many components that are easy to use (like buttons), you can customize them as much or little depending of your needs/requirements so no more time spend searching different packages with similar features - just one! And their support team helps in every way needed at any moment :) The price could be lower but I understand this choice from what they want do build up an active community around semantic-ui react instead than being only another "theme" available out there if people didn't know about semantically ui before using other themes like bootstrap etc.. This theme will help those who don'y have too much knowledge or experience when building web interfaces because all elements look very clear without having specific learning curve required by others libraries such us twitter boostrap framework...