The functioning of web.whatsapp.com app is pretty much similar as like whatsapp application.
the Service & Suport is great as per my web.whatsapp.com experience.
it is the best way to share information and chatting with the help of computer or laptop.
the main thing and the best thing is its design and its usability. design is pretty much like its phone application. sometimes it takes time to load the web.whatsapp.com online application but after all its amazing and interesting.