I first discovered this product after listening to the Empire Flippers podcast. I've used their valuation tool a number of times to get a ballpark estimate on what a website is worth, and it has been incredibly valuable. What makes this tool a little different, is that it asks for the monetization method up-front, and then determines a value based on that. It doesn't simply ask you for your revenue and expenses like most other website valuation tools - this is a big differentiator and it's the reason why I use it so often.