Any opinions on Javascript/CSS minifying gems?

I see asset_packager, jamit and smurf available to handle minification
of
javascript for production. Any opinions? I am really looking for ease of
implementation as what I have is not that complex, just a number of js
files
and a few stylesheets. But I like the idea of a gem to handle this so I
dont
have to think about the process once in place between dev and
production.
Keeping the non-compressed files in development is also very important,
of
course.

David