I read the quick start rules and Muddy Mayhem. We've played about half of MM with the new pre gen characters. Its a fun adventure. I'd put it at an 8/10, similar in fun to several of Wills other modules. Mall of Doom gets a 10/10.
If you include Sandbarra town this adventure will take around ten hours to play with 5 characters. The Elvis stuff is funny and campy. I am getting tired of Skullocks and could do without them in future adventures. One of the few drawbacks of TME universe is a heavy reliance on mutated humanoids like garnocks, moaners, skullocks etc etc. They are all sort of a variation on LOTR orcs.
I find that the combat is the most tedious part of gameplay. I enjoy the speaking interactions and puzzle solving elements.