CGI::Fast first and CGI second so that if there is any colision, CGI wins.

Unless you have a library conflict with broken installs which is actually pretty hard to manage (some things installed in one place and related others at a different version installed in another place). This is not an issue and you should not even load CGI because it is misleading. CGI::Fast has already done it internally. And it's backwards. First loaded, where code overlaps, wins, not second. (Update: to clarify, I mean code packages. Once loaded, they aren't reloaded without gymnastics.)

From the CGI::Fast POD (and code, POD can lie) – CGI::Fast is a subclass of the CGI object created by CGI.pm.