Well, JaymanAU, I'm afraid that I can't help you too much here, but I did not want you to thing that you were being ignored.

The SanDesting Hilton is, unfortunately, way too close to home (~35 minutes) for me to have ever stayed at it. So take everything I say as very general, OK?

I went there for a conference in 1990 or 1992. The property then was very clean, impressive, and nice. But again, I didn't stay in a room, just a conference room.

IN GENERAL, offtopic to your question, there are several potentially nice things about this Hilton...
1. You are in Sandestin, not Destin. You will therefore be out of the worst of the summer tourist traffic. This is GOOD!
2. There is lots to see and do in the Sandestin area. There are lots of shops and places to eat there..including Elephant Walk, which used to be a very fine restaurant and prob'ly still is, I just haven't eaten there in several year.
3. You're a hop and a skip from great eating and pretty uncrowded areas in Blue Mountain Beach, Grayton Beach, etc. Plus pretty uncrowded beaches in that direction. Oh, yeah, there's Seaside, too, where they filmed "The Truman Show." If you go there, be sure to visit Modica Market. Grab a deli sandwich or some GREAT crab or shrimp salad, cross the road to the beach, and have a Gulfside picnic.
4. You're close to Silver Sands Outlet Mall, which has some good shopping/deals. (Don't know if this interests you or anyone that may be with you, sorry)

I won't go on, but hope the above makes up for my not being to give a valid comment on the Hilton itself. If you want more advice on places to go/things to see, feel free to email me!