[SalesForce] eclipse + force.com ide plugin launch freeze problem

Some of us have been upgrading eclipse to juno, which is giving a lot of problems starting up. Specially after also upgrading the force plugin to winter13/api26 Sometimes it will load and launch (and then I try to not reboot for as long as I can), but 90% of the time eclipse will freeze while loading.
This typically happens when "Loading com.salesforce.ide.core" is the displayed status above the load-bar.

My eclipse ini file:

-startup
 plugins/org.eclipse.equinox.launcher_1.3.0.v20120522-1813.jar
--launcher.library
 plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.1.200.v20120522-1813
-product
org.eclipse.epp.package.java.product
-product
org.eclipse.epp.package.jee.product
--launcher.defaultAction
openFile
--launcher.XXMaxPermSize
256M
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
--launcher.defaultAction
openFile
-vmargs
-Dosgi.requiredJavaVersion=1.5
-Dhelp.lucene.tokenizer=standard
-Xms40m
-Xmx1024m

I have some increased values based on posts I found trying to find a solution, to little avail. Other members of my team, having defaul ini files, also have problems launching eclipse.

Deleting the .lock file from the workspace folder as suggested on some websites, does not help.

In the meantime I've installed the standalone force.com IDE application which runs fine, but I'd like to return to using eclipse. How do I maintain eclipse & the force.com ide plugin working well together, while doing upgrades of both when they are available?