I used just five, purely for the sake of character. I don't imagine them to perform miracles of any kind, but what I wanted from them were not miracles, it was the feel. Plus, I really like wolf riders, simple as that.
I used ungor arms on these, which was fine until I started gluing on the heads. They are just too big. If you can, use the crew heads from the arachnarok spider kit, I think they will look much, much better and some dry fitting seems to reinforce this theory.
I also added some bedrolls and other gubbinz - really wanted to pull off the 'nomad' feel.