I don't know about Eclipse being better. I switched to IntelliJ two years ago and I love it. I find it much better, faster and less buggy compared to Eclipse.

It depends on what you are using it for. IntellJ's maven integration is to die for. Eclipse has a better auto-completion engine.

IntellJ is far less resource intensive but eclipse has some features (mutli-projects in one 'solution') that IntellJ won't add.