Concept: Concept is good and try tried so much thing to develop
Layout & design: Its is good app and easy to use.
Features/Functionality:it is good and all are working correctly
Usefulness: It is not at all useful Now a days this site or organization not working as they use to be. No jobs and all most all company fack information. I am not suggest to go for Amcat other rhen you can go for others sides like Elitmus, cocubs.com. so many.
Thanks
Good Luck!