and Delta partners. Because of how much I fly, when there are problems, which is usually about 10% of the time, Delta is usually really helpful in making changes to my flights to accommodate my/my families schedule. Even when I didn't have status, they were still usually very helpful. I've had worse luck with United and their partners to the point I won't fly them. And basically all airlines from Mexico south to Argentina are poor when it comes to changes. I've had a higher percentage of challenges on flights when flying to South America unless it is American Airlines.