I think the Hilton is great. I feel bad about subsidizing Paris Hilton's extravagance, but it is by far the best hotel we've ever been to. The layout is the best by far, we have TV screens next to all the room doors that we can use to display maps and schedules, the ceilings are really high, the park has been cleared of hobos, there's free parking readily available within a few blocks, and the staff has been really, really nice. The Doubletree had more rooms, more event space although a poorer layout, and a really nice staff too, but they were kind of lacking in all the other areas that I mentioned, and the ceiling in main events was uncomfortably low which was a challenge for the setup crew.
EDIT: And while I can't argue against anyones opinions or personal feelings, I disagree about the downtown location being "extremely unsafe". Show me some insane crime rate statistic and I'll defer but I know from how much time I've spent around the Lloyd Center area that the crime rate there isn't that bad. I've worked at the Pacific Center tower a few blocks away for about a year and went to the mall on most days for lunch, and I know nobody I worked with would describe the area as unsafe at all.