TL;DR I got 10.2-STABLE to boot on Model B+ and 11-CURRENT to boot on Raspberry Pi 2 Model B.
It turns out it was harder than I thought to get the image to boot. First of all there was no video signal out so I had to connect to the Pi using a USB to TTL serial cable.
What I found out was that the 10.2-STABLE image only ran on the Raspberry Pi model B, got Unknown Filesystem error on Raspberry Pi model B+ and did nothing at all on Raspberry Pi 2 model B. See this pictorial bying guide forum post for more information on the different models.
I did get the FreeBSD 11-CURRENT to boot on Raspberry Pi 2 model B. For now I was satisfied with this since the WiFi dongle I wanted to use didn't work out of the box with FreeBSD I decided to put it aside as a candidate OS for now.