Chevy Chase made a very brief cameo (which I really didn't get).
Perhaps the biggest problem with this film was the nature of the time travel. In the original film, time travel is stumbled upon by the dropping of a terrible Russian energy drink into the hot tub controls. In this film what enables time travel is some experimental element invented in the future. They never explain what happens to the energy drink. At one point the characters are explaining how they can get the element before it has been invented and what not. Very confusing, considering they should just be able to go buy some of that Chernobly.
What gives? Was this just a cheap plot device change to make conflict in the film?
The other odd thing about the film was it totally upended the ending established in the first film. At the end of the first film it is assumed the characters are all better people after changing the future. The second movie indicates that no, their lives are just as crummy, even with more money and success. Corddray and Duke get more father-son time to resolve issues that had developed since the end of the first film. Webber is still struggling with his marriage...etc.
I think this film undermines the original one. Yes it is fun. Yes it is as raunchy and campy as the first, but the story was no where near as good as the original.