retina.js has helped us in improving our website content resolution for mobile users, which have been a pain point of ours so far. I am using this library since last one year now without any issue. The team over there are very active and supportive when you need help or suggestions regarding your code. Nothing much to dislike about this library as such. We had some issues with resolution of content on desktop but after we used retina.js everything was fine. Our site is getting good traffic from all around the world therefore, increasing my knowledge base every day.