Overrated. Having visited petroglyph sites in California, and Nevada, this one is just A-OK.
Pros:
1. Paved road to the site.
2. Nice visitor center
3. In Phoenix residential area, easy access to I-17.
Cons:
1. Admission is expensive. Use AAA membership card to get some discount.
2. Petroglyphs are too distant, and hard to see.
3. Petroglyphs are faded
4. There aren't too many petroglyphs here