Digital 3D vs IMAX 3D

I was looking at the times for Avatar and I noticed you can see this in digital 3D or IMAX 3D. Obviously IMAX is the bigger screen but is digital 3D better than the IMAX version or does it not make a difference.

IMAX IMAX IMAX

Mostly for the THX sound man....cant go wrong

saw it in Imax 3d last night.  Worth the $14

Be warned that there are a lot of "fake" IMAX out there. There are only a handful that have true IMAX with the giant screen. Most out there are scaled down but have the superior IMAX sound.