How powerful is my stock stereo?

I have a 2004 Toyota Camry Limited Edition, and the stock stereo is a JBL 6-CD Changer. Simply I would like to know the specifications on power of this radio and if it would be better for me to buy an after stock or not. If not maybe a stereo website or source where I could find this information. If I get an after stock stereo the plan was to purchase a Pioneer Touch Screen so I would be able to gain an ipod hook up. Please give opinions, information, or better ideas.