Thinking About Taking A Zero-G Flight

I'm thinking about taking a Zero-G flight sometime soon.  What the plane does is simulate weightlessness (Zero G), moon gravity (1/6 G), and Martian gravity (1/3 G) through flying a series of 20 or so parabolas.  This method is what NASA uses to train its astronauts for spaceflight.  John Carmack, of Armadillo Aerospace, reports that it's a blast and was well worth the 3 grand for him (he has a rather more substantial pocketbook than me).