The Safari Park is great. One of the main differences is size. The Safari Park is about 900 acres, and focuses on mostly African and Asian animals. There are field exhibits that you can walk on the outside of to see the animals, but some can be hard to see depending on where they are in the exhibit areas.
The Park also has awesome lion and tiger exhibits (Tiger just opened last Year), along with Ca Condors and Cheetahs.
If you have any specific questions, you can PM me. I work at the Zoo, but have been loaned to a couple of departments at the Safari Park over the years