Is this plugin a must have? This is up to you. The normal like button is also enough just to say "I like it". But if you want to have more different reactions you need this plugin. And you need it also if you want to have a feeling of facebook in your website. What is the advantage? Your members will accept your website easier because they know this system of expressing their opinion. Under these aspects this plugin is a must have. We like this plugin and it works really good on pc and mobile. Thanks for an awesome plugin.