In some environments this may not be a good thing.

Most Solaris machines come with Perl and this may be rather ancient. However it may be better not to play with this and to install your own in another location.

Different versions for different jobs and I'd rather have control which I want to use.

What happens when run under cron rather than at terminal?

Edit OK so this doesn't answer the question but others have done that far better than I can.