I know it is good but I don't have the numbers. freebitco.in PR probably does as they do all the marketing side of things.

The suggestion to put it on the site rather than through the emails is just missing the whole business side of why we do everything. When a business gives something away it's because they get something in return. We give a free roll every hour and in return, you keep coming back to the site where we can market the gambling to you. There's no point in adding another free giveaway that does the same thing. So we introduced WoF which gives you something for free in return for engaging with our promotional emails.