The Sheraton is a good hotel. I actually stayed there once on a priceline stay for pretty cheap and the rooms are fairly good little bar and restaurant on site that although wasnt very busy when I was there was decent and convenient.
The Hilton Garden Inn is relatively new so the rooms are obviously in good shape and I would say it is a typical Garden Inn with nothing bad to report about it but then again nothing exceptional. Seems like it was a little farther down the road and closer to restaurants etc.
Hilton Suites is the most impressive looking from the outside and in the lobby. I was impressed by the service also. I did think however he rooms was a little gloomy. This hotel is setup in the rooms like a embassy suites with a seperate living and bed room. The furnishing where older and the lighting was bad in the room I was in (dont know if they are all like that but I am Diamond with Hilton so wouldnt think I would get the worst of the lot) so it was a little gloomy. The prices at the restaurant etc where slightly higher at this hotel than the others but still reasonable. I wouldnt mind staying there again but wouldnt pick it unless it was more convenient.
The Holiday Inn was a little more worn and as mentioned before may be a bit out of the way. They have a decent restaurant and bar on site but service for me at both was not great. I only stayed there as I was having a meeting in the offices next door and walking across the parking lot was worth the convenience but given the hotels above I would not select the Holiday Inn as the rooms where more run down than the other hotels and service was average at best. It was also the busiest of all of the hotels I mentioned above.
My personal choices would be the Garden Inn or the Sheraton. I would return to any of them though.