The space requirements are slim. That's on the big side, but reasonable considering the number of features and enormous documentation. Also, there's support for mobile computing applications. These features are hard to find on a mainstream IDE for Linux, not to mention from a vendor that's had such a long track record for creating IDEs. Choosing an IDE for development is a serious decision.
Most people find one and stick to it.
After all, switching means you'll have to adjust to the new environment, learn new features, and customize. So I look for the little things, such as the ability to change your background color, shortcut keys, and fonts, or choose where the menus are placed and how they pop up. It doesn't really matter how advanced and fancy your IDE is if you can't live with the details. Borland has done a great job creating a useful and productive environment. Overall, the JBuilder is very easy to get used to.