I bet they work. When reading gambling topics here, I read only gambling topic that I saw have (or had) signature campaigns here Duelbits, Stake, Roobet, BetFury and maybe Sportsbet (but they are mostly football oriented, and their page is not allowed to visit with my IP, so I check them rarely) - all of them are one of the most viewed topic (topics that are still active). If I plan to make a deposit and have fun, I would consider these casinos to be first in my list. Imho, signature campaigns really pays off.