This strikes me as no easier than rvm, but less clean (installations go to /usr/local, no easy way to switch between various ruby interpreters or gemsets, harder to uninstall, etc.).

Why not just do this?

    1) Update whatever requirements you need via APT tool of choice.
    2) Install rvm
    3) Install ruby-1.9 using rvm
    4) gem install rails
    5) Write great rails app.