Brilliant.
Nothing less suffice. I guess I have seen about 70 MST3K films over the years, and this has to be the best. Stuff like "Future War" and "Outlaw of Gor" came close, but the quality of the jokes - and the sheer volume of them - makes this an almost non-stop laugh.
Also worth mentioning is that Mike and the bots laugh and snicker a lot more of their own gags along the way so you really get the impression that they enjoyed doing this more than others. This cannot help but make you laugh a bit more as well. Also the gags are quick to comment on the stuff that you, as a b-movie fan, spot yourself. Those are the best gags in my opinion.
The movie itself is suffering from mediocre acting, lack of extras and limited sets/locations - but knowing how the movie was filmed and that the budget was so limited (see trivia about the movie) then nonetheless a good effort - but not the director's best.
So on my scale with about 1400 films in the bag that would be a 4, since it at least progresses somewhat coherent and you get the overall idea. Also, only a handful of bad cuts. For the MST3K version it would be far up the other end of the scale. Go see it!