I would go for a Wacom – even though other brands a good too. As long as it has pressure sensitivity you should be good.
The Wacoms are generally more expensive, but also much better in my experience. Many pro animators opt for a Wacom Cintiq (it has a build in screen), which is the VERY expensive solution. This is NOT needed in your case I would imagine. Any smaller Wacom would do just fine I would say. Preferably an A5 (medium) size.
Just my thoughts. Maybe others have better recommendations?