Back when Hilton and Southwest had decent programs, I liked the double dipping. I use to do a lot of cheap one night stays and could get a half credit on Southwest plus Hilton points which until the deval were valuable for me.

But the Southwest program is no longer valuable for me (and Southwest isn't even a partner with Hilton anymore even if they were), but with the exception of LA, Hilton seems to have convenient locations to all the cities I travel to and the free breakfast at almost every property is nice. I also like the Delta MQM 4q promo they have had the past few years.

I use SPG for my backup plan if I know I will require a late checkout. Hilton won't guarantee me a late checkout. I get a 4 pm checkout guaranteed at most SPGs with their partnership with Delta.