I'm interested in knowing the differences between these two versions. If I would opt for the latest, which o开发者_JS百科ne would that be?
Take a look at the Helios New And Noteworthy for a quick visual overview of what changed in Helios (3.6).
If you really what to know the details, you can look at the closed bug / added feature list.
Galileo is version 3.5.*, Helios is version 3.6.*. Helios is the latest.
You should use the more recent version unless you depend on something that only exists in an older version. In that case, try to kill the dependency ASAP.
As for which one is better, I don't know (and won't answer). They're very similar.
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