Don't go on the Fourth of July weekend. It was HOT & crowded (and I'm used to HOT since I live in Louisiana). We drove to the main attractions, but had to walk forever to get to the lookout points because there was no place to park due to the vast number of other tourists doing the same thing we were. Our experience might have been different if we had visited during a slower time. The views were fantastic (when we could push through the crowds to get a good view.) If I go again, it will be to the north rim.
Cons: hot , crowded, unfriendly