Since last October binary packages have been available for FreeBSD (http://lists.freebsd.org/pipermail/freebsd-pkg/2013-October/000107.html). Before that, they had some trouble, preventing binary packages from being published.
At this moment, is there any reason not to rely on the binary packages mirrors? Is there any chance that a security breach would be found and the binary package disappearing again?
For a new installation, does it still make sense to build things from the ports tree yourself, or is it stable enough to use only binary packages (provided you need everything with default compile flags)?