Not as good as the first one...
The jokes are just a little tired, and we saw it all done once, and very well. Also, the whole thing with Greg and Martha was a bit forced.
That said, this is still a great movie. Maybe some people don't understand why both of these movies are actually so funny. They don't seem to get just how saccharine the Bradys were even when the show was fresh. I guess I can see how if you don't get the overlying inside joke this might not make much sense, but it really nails just how silly The Brady Bunch actually was. Times were changing fast and the Bradys never really seemed to catch up, even at the beginning.