HI and HGI are often the only Hilton options in some of the out of the way locations I visit. I will always choose the HGI because the breakfast is better(cooked to order), I can eat dinner at the bar in the hotel and have a drink or two with it and earn additional HH points for charging the meal to the room. Its also nice to have the pantry available.
There are some great new HI out there but the HGI product seems to be more consistent.