Since everyone is pitching their favorite books on abstract algebra, here's mine: http://a.co/fg0OUdG http://a.co/fg0OUdG. I'd love to hear what differentiates

Since everyone is pitching their favorite books on abstract algebra, here's mine: http://a.co/fg0OUdG http://a.co/fg0OUdG. I'd love to hear what differentiates this book. Why should I read this one instead of the existing options? Is it because Sage is used?