Well, according to the OpenGL API you should use DYNAMIC_DRAW.
STREAM
You should use STREAM_DRAW when the data store contents will be modified once and used at most a few times.
STATIC
Use STATIC_DRAW when the data store contents will be modified once and used many times.
DYNAMIC
Use DYNAMIC_DRAW when the data store contents will be modified repeatedly and used many times.
Make sure to update the VBO with glBufferSubData()