Matt, I would respectfully disagree. I have lived very close to a lot of different dunes In my life (Glamis, Little Sahara UT, Coral pink UT, St. Anthony Id) and have spent much time at all, and I am here to tell you that St. Anthony is the king of them all. Nothing is steeper or taller than st. Anthony, only LS UT is close. The views are great with the Grand Tetons to the east, and all the lush green farm land spread out for miles. The dunes are not very busy, and because of that there is not a strong law enforcement presence.
There are other reasons too, but you should come see for you're self.