Mohair has long fibers but is a bit less durable than wool. For this reason, it is often blended or plied with wool or nylon to give extra strength. You may not want to use mohair for making socks, but it is great for just about any other project.
All animal fibers have the possibility of pilling, and this is somewhat determined by the way the yarn is spun or manufactured. For instance, a single-ply yarn might pill more readily than a yarn with more plies (or strands spun together).
Like wool, mohair will felt easily, and makes a very fluffy item. Check the yarn label carefully before choosing a mohair for felting, since they are often blended with nylon, as discussed above.
Mohair fiber is susceptible to attack by moths, so use mothballs to protect yarn, fiber and garments. If you don't like the odor, periodically place the yarn or garment in a plastic bag in the freezer for 48 hours to kill moth larvae. You should also air out stored fibers in the sun every now and then.