Building from ports is really easy.. In the 10 years I've been using FBSD I only encountered maybe 2 or 3 times where something didn't want to build. Csup'ing the ports tree fixed that.
Building from source has the advantage of selecting the options you want/need. It's also slightly more up2date compared to the pre-build packages.
And you really don't want to know how many times I've re-installed everything from scratch the past decade
Tip: Create a seperate partition for /usr/home. That'll make re-installing the OS simpler, without nuking your files