CPANPLUS should work with core Perl, although it is a lot happier if you will let it install some modules during setup, especially on machines where it might be difficult to use binaries. Certain options, such as md5 checks, require that module be installed. However, if you don't want these modules installed you can decline them during configuration (if you do want them, CPANPLUS will handle the installation before it installs itself).

As for the normal prereq handling, CPANPLUS allows you to select whether you should always follow prereqs, never follow prereqs, or prompt for each.

CPANPLUS will decline to install new versions of Perl. It will let you download them, if you like, but because Perl should be installed quite interactively, CPANPLUS insists you do it yourself.

One advantage you may find to CPANPLUS--which I mention since you talk about production servers--is the programmer's interface which makes it easier to maintain modules on multiple machines. You can set up an install script to install the same modules on multiple machines (and handle known issues with modules and the like). CPAN.pm does allow this, but by poking through the shell. By comparision CPANPLUS is a lot cleaner, since it was designed with the programmer's interface in mind (shells are just layers on top of the interface). Check out Backend for more information on the programmer's interface. It's worth noting, however, that this is version .036, and the interface changes significantly (which it may continue to do until release 1.0) in the upcoming .04 (in particular, return values become objects).