I used eclipse to code java every day for 5 years. I used it on windows, linux and OS X. During that time I upgraded computers a few times. Each time I upgraded I was optimistic that my shiny new machine would make eclipse run at a tolerable speed. Having a language that was succinct enough to not need a beast like eclipse was one of the main reasons I originally switched to ruby. Using something simple like textmate sometimes means I have to go the long way round when I want to perform a refactor but at least I know when it's going to be slow. With eclipse you can do something as simple as open a file and have to endure 30 seconds of freeze. When you need to get something done fast that's painful not to say stressful!
Either you have a v slow machine or you had some major configuration issues with Eclipse or other services running on that machine. Even on a 1.4GHz Core 2 machine on a large java project, source files open < 1 sec.
