Ocean Course and Heron Point in Sea Pines are both really nice.  Also, I've played the Fazio Course at Palmetto Dunes and it also was really nice.  Harbour Town also, but I'm sure that is the obvious one, lol.  Of those, I think the Ocean Course is the nicest.  I'm hoping to get back down there later in the year. 

Have fun.

I've been really fortunate and have been able to play a lot of top courses (Harding Park, Sawgrass, TPC Boston, Kapalua etc...) and The Ocean Course is just outstanding.  I played in early December, and the weather and conditions were great.  If you can swing it, it's worth the trip.  There's something special about it, and the views are unreal.

I've been going down there for 10 years and always play Fazio,HH National,Old South and Harbour Town. All enjoyable and challenging . Island West is a little off the Island (45 mins) but worth the trip.. Have a great time...

If you have connections, play Spring Island.

WW

May River Golf Club in Bluffton is a must play.

I will second Tyler's recommendation of the May River Golf Club!  Pricey, but always in pristine condition and a lot of fun to play.

I have played Harbour Town and Heron Point.  They are both nice.  Harbour Town is worth the money just to play where the pros play.  I have also played all 3 courses at Palmetto Dunes.  You can't go wrong with any of them.  The Jones course at Palmetto Dunes is my favorite of those 3.  The 10th hole is right on the ocean and makes for a nice view.  Enjoy your trip!