What is wrong with prepending own's Perl bin dir to $PATH (not root's, agreed)?

Gah. I really need to create an account here so I can edit my posts. You're right, thanks for the correction. I should've written "Do not add /opt/perl/bin to root's $PATH". As you point out, prepending it to your own (not-root) $PATH works great.

The only reason I can think of that you might not want to add it to your own (not root) $PATH is that, when logged in as yourself, you'll get used to always automatically getting /opt/perl/bin/perl, and then when you log in as root, you'll run some code may forget that you're back to getting /usr/bin/perl. :)