Watched this last night and, honestly, did not do it for me one iota.
I'll preface by saying that I'm not really on the Nick Cage bandwagon. He can be a fine actor given the right role but this recent movement of putting him in scenario x,y or z and letting him be insanely over the top just doesn't do much for me. It's just crazy randomness for the schtick of it and there's nothing really there that entertains me. Still, I wanted to give this a shot because I love splatter horror comedies but I was very disappointed.
The major strike I put against Willy's Wonderland is the complete lack of tension. I fully understand that the selling point of this movie is Cage going nuts against killer animatronic animals but when his character is so ridiculously powerful against them there's just no threat and no entertainment unless you're into seeing Cage acting nuts. The fight scenes themselves are poor and really only one 'finishing blow' of one of the animatronics felt visceral at all (and it was, IIRC, the second one or so).
Outside of the main purpose of Cage v. Animatronics, the acting from the rest of the cast, a set of young adult/teenage lambs to the slaughter, is poor and forgettable. The plot is laughably bad and I was pretty astonished we got not only one blatant exposition scene but two unnecessarily shoved into the movie. The effects were also forgettable, though I did like the design of some of the animatronics themselves in puppet form; there were too many of them, they would have felt more memorable if you could concentrate on only 4 or 5 of them rather than 8. The music was ho-hum although the demented kids' songs were a nice touch. I did quite enjoy the gag of Cage replacing his goofy employee shirt after every battle, that was a nice touch.
If you're not into Crazy Cage, I don't think you'd get much out of having a birthday bash at Willy's Wonderland. If you are, you might get a kick out of seeing Cage dismantle some blood thirsty animatronics. 1/2 Star out of Five for me.