My notes from when I first started Unix 8 or so years ago have
    gzip -dc somearchive.tar.gz | tar xf -
as thee way to unpak tarballs.  Even used it so many times that I got tired
of typing it and set an alias for it.

In recent months I've been slowly revamping old installations, and I
notice there are a lot of ways to do the same thing:
    pax -zrpe -f somearchive.tar.gz
    tar -czf somearchive.tar.gz
    cat sys.tar.gz | (cd /path ; tar zxf -)
Probably there are a bunch of ways I haven't even come across yet.

Are there REASONS why a certain archive might be unpaked a certain way?
Or is it all personal preference?

-- 
henry nelson