Maybe if the US properties are your main emphasis, IHG may not be the best choice, though it depends on where you travel. I enjoy the IC SF, though it doesn't compare to the high level Asia IC properties I have stayed in. But for SF, it's location and lounge make it my favorite when I'm back there. Of course, my Thai GF keeps asking when we're going back to the IC Hua Hin as she loves the breakfast, though I don't find HH very interesting as a beach location. But back to US properties worth staying at: IC LA downtown; IC Clement in Monterey, my son loved the IC Boston (maybe it was the free minibar with my RA at the time my sister liked the IC Chicago Miracle Mile, though I usually booked her into the HI Merchandise Mart as I really don't like her very much, but the price was right. I do prefer the Park Hyatt in Chicago, but that's another level. IC is definitely better in Asia, in fact most HI's in Asia are great as well, so it all depends on what you like.

I don't find Conrads to be anything special, and there don't seem to be very many left in the US. I did enjoy the Conrad Brussels some time ago-appears no longer a Conrad. Hated the HK Conrad though.