Just bought one last Saturday from Astro Megamall. Got the voice changer for free. My daughter loved it though your voice wouldn't really match that of a chipmunk. Among the three voice options, I would say that the "Kid" setting is the one that closely resembles that cute chipmunk voice. The other two options - the "Robot", and the "Boy" are a bonus.
With regard to the DVD, I would say that I kinda felt that there was something missing. I couldn't find in the bonus features any clip which shows who the voices behind the chipmunks were. For P550.00 medyo ok na din.