Its a really good question, tbh. I've used Eclipse and other Java IDEs for years and I consistently feel like Eclipse has had the worst UI design of them all.

Its a really good question, tbh. I've used Eclipse and other Java IDEs for years and I consistently feel like Eclipse has had the worst UI design of them all. But it is also the most popular, even among the free IDEs. Apparently the community's UI preferences are different from yours and mine? In any case, while there does appear to be a small latency penalty, there really is no rule that a Java based GUI has to be ugly. I find both the IntelliJ and Netbeans IDEs to be pretty nice.