On top of that the article makes the classic mistake of saying it pays for itself if you spend $166 a month, but it only really pays for itself if the marginal value of using the card over a generic 1.5% cashback card on the things you can't get 3% for already is more than $5 a month. Things like high cashback percentages for the first $X a month in specific categories make this intentionally hard to calculate, and are part of why I never really got into optimizing my credit card benefits. It's obnoxiously hard to compare.