Shelley is correct. My DH took me for my birthday this year.
First off, the show is pretty funny and I'm a tough customer. Let me summarize it this way:
If you like Broadway musicals and you're familiar with Monty Python and like them (and you can justify the expense), you should go.
On the other hand, if you're not crazy about Broadway musicals and you love Monty Python and are very familiar with them, skip it and rent Holy Grail again (and save about $194). (This is my category).
Hope my DH doesn't see this.