User blog comment:Sakuraiayano/30-Day Rare Summon Question (just curious)/@comment-76.236.39.4-20140117070305

Some have argued that your chances of getting a 5* is 1.3% * 30, others have have argued that its just 1.3%. Replace 1.3% with the actual chance, dont have it memorized. From my experience, the first 30 days yielded no 5*. I'm about half way through the second 30 days and I got Kesaran 5*. There are extremes: someone on the wikia here got 4 5* in this 30 day offer, but many got zip. Honestly, I think the people who get the 5* during this offer are more likely to share it than people who don't get a 5*. So essentially it depends on how you think your luck holds, but I wouldn't hold my breath. I still thought this was an alright deal because you get 5 6-packs for the price of one.