"To all beginners, you don't need these extras, they're just extras to save a few keyboard strikes ... for a very very small amount of perl developers ( less than %1 )"

I'd like to know where you got your 1% statistic from :) I believe they do far, far more than just save a few "keyboard strikes"... they help prevent you from hosing your system's Perl, and in some cases, your system itself.

I know more people who use perlbrew than I know that don't...

I tend to agree. It's unnecessarily difficult to set up perl so you can install modules in a sane manner. That said, you don't really need any 'brews until you're ready to start installing modules.

++.

To further that, both perlbrew and berrybrew allow you to make copies of instances, so that you can do this:

berrybrew install 5.24.0_64
berrybrew switch 5.24.0_64
[download]

... do a whole bunch of stuff, install all of your favourite modules etc, then:

berrybrew clone 5.24.0_64 configured_perl_template
[download]

... do more stuff on the 5.24.0_64 instance, and break it horribly, then:

berrybrew remove 5.24.0_64

berrybrew clone configured_perl_template dev_instance_1

berrybrew switch dev_instance_1
[download]

Then break this instance, re-clone the template again, and you start with a 100% configured instance to your liking repeatedly.

That example was berrybrew, but perlbrew has the same functionality. I wrote clone into berrybrew so I could have separate instances, pre-configured, to separate development testing, and for keeping separate projects separate, under custom named instances.