I stay here about once a month and it's my preferred hotel in Savannah. I can't say there's really anything special about the hotel itself - rooms are fine, as a Diamond I've always been at least given a river view, usually either a mini suite which has an extra sitting area and a couple of times a top floor corner room which has a huge outside balcony / area (it's about the size of the room itself so calling it a balcony doesn't seem quite correct). It's the staff and service there that I like so much. They make the guests seem very welcome and after just my second stay many of them started recognizing me.
Don't know your GP status but Diamond's get free breakfast in the restaurant as l'etolie said. I'm not normally a breakfast eater but the buffet is definitely an above average hotel offering and I usually do stop by when I'm at this property. GP members are also given a card to show at the bar which gives you happy hour prices all night long. And the bar has Guinness on tap so I make good use of the certificate. Turn down service comes with a couple of lilac flavored chocolate which are quite tasty.
Parking is valet only at, I think $22 a night. The Whitaker St garage is right across Bay St though and is $14 a night. Definitely within walking distance to anything you would want to see in downtown. Can't speak of the gym because Savannah weather is usually nice enough to go running outside.
The Andaz is a block away or so and the rooms there are more modern and a bit nicer but I much prefer the service at the HR which is why I stay there whenever they have my rate available.