Ready Clean is a great product, been using it for years and have never "failed" a test. I've used it for jobs and for probation and it has never failed me yet. It's sold at just about any party store, head shop, and even hydro stores. It usually costs around $30 but it is definitely money well spent. That wizinator thing is a joke, mainly because of the temperature, and if it is for probation, they usually have someone in there watching you so you don't "cheat it". The label tells you to not take in any toxins for 48 hours, but I've actually smoked 6 hours before probation, drank the stuff, then followed the directions and drank about a half gallon of water to piss out anything left, and it has worked without fail every time. I don't recommend smoking so soon before your test, just saying that I did once and the stuff still worked, luckily. There are a million ways and products to beat a simple urine test, just have to choose what you think will work. They even make a stronger drink for bigger people such as yourself. Try it, it works!
http://www.testclear.com/product2.aspx?Product_ID=26