Hi chuckly,
The better options and possibilities I’m aware of in the Hilton head Island area are listed in post #2 here.
The first (and quite possibly the last) place I would go is The Charleston Bedding but I’ll also take a look tomorrow to see if there are any other local possibilities that are closer than Savannah for the rest.
As you probably (hopefully) know I wouldn’t walk through the front door of Mattress Firm 
Phoenix