In the "-I" approach the biggest consideration comes from module movement. If the modules move from /some/location to /another/location only one place (/usr/bin/perlcron) needs to change and all the programs using those modules are repaired. When using findbin/lib each program itself has to be repaired. At one site i was at we moved boxes 4 times in about 7 years, each move with changes to the names of the file system paths. In that case it wasnt for cron, but to ensure a working production environment. As soon as i fixed the initiator-script all the processes worked under the new locations. I also use this method still on my home boxes, various windoz and linuxen, each with its own customized initiator script to let it run in that environment.