5.8.x does have many better features than 5.6. However, because 5.8 is newer than 5.6, there could be some bugs with the distribution, which could be fatal (either security wise or stability wise). It's just a matter of how cautious you want to be. If you have something that you *know* works, then when you upgrade the (perl) engine, you have to re-test the entire suite of software to ensure that you haven't broken anything, which is a serious issue if you are in a production environment. If you're just writing one-time toy scripts, then using a bleeding edge version of software could work to your advantage if it has a feature you can exploit in your favor.

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Zak