Perhaps consider DL, but the "much better" statement is highly subjective, and even assuming same service standard, which program will be better is going to vary highly on priorities and where one flies. Personally, the UA merger mess has not been too bad for me - despite hearing some to the contrary, I'm still treated extremely well as a 1P, and the couple of delays I have had since March have been relatively minor in the scheme of things. On the occasional DL flight I've taken, they've always given me reasons why I don't want to buy another ticket with them again. And reports are that if you actually want to use your miles, SkyPesos are not the currency you want to be collecting.