I'd most likely chose the Doubletree Sukhumvit over the Hilton, given the Hilton is usually 33% more expensive. (40k vs 30k pts/night) I way prefer the Doubletree's pool. However, the Hilton's rooms are bigger and nicer and it has an executive lounge. It'll totally depend on what is of value to you. If they were the same price, I'd chose the Hilton. (Also note that I've never tried the Doubletree's breakfast. The times I was there were pandemic era, when they were sending all guests to the Hilton for breakfast. You can walk between the two hotels.)