I supposed I'm biased, as SDC looks to be my home DZ. I'm still a student, and don't have any other DZ's to compare SDC to, but I can't imagine there being any better.
The food is delicious, the non-skydiving entertainment is great (for my lame friends), and the people are among the most friendly and diverse that I have ever met.
The facilities are all top-notch, and safety is of course everyone's greatest concern.
For me, I was sold on the place when I discovered that some of the skydivers have bought trailers and simply LIVE at SDC whenever they can get enough time to jump.