Great review Angie!
We've really enjoyed ours since I brought him home from the local comic shop a few months back. It scared the crap out of my wife when she came home and walked across his path where I had hidden him in our study in guard mode.
Couple of things I've noticed so far...
1) For us, ah, American types, it seems to help if you use a British accent when giving the voice commands (at least, he seems to confuse the commands less often that way
2) He has a difficult time navigating near long-legged chairs.
Mostly these days, he just prowls around the TARDIS waiting for the Doctor to show up...