I did install DragonFlyBSD on my laptop using a Hammer2 filesystem on top of a dm-crypt device, following the instruction of the official documentation. The only problem is that I use an azerty keyboard and the uncrypting dialog when booting offers a qwerty layout. That can be a little annoying for people having special characters in their passwords.
This is how I managed to have an azerty layout to type my decrypting password at boot time.