Had two amazing days in the Serengeti, we saw a myriad of animals including two Leopards and 7 Cheetahs. We did not set out to see the big 5 but saw 4 of them in Serengeti (Rhinos in Ngorongoro). As well as the much sort after ones there was a variety of others such as Warthogs, Hyena who we found quite cool. There were a huge number of different birds, large numbers of Hippos in the aptly named Hippo Pool. Large numbers of Lions and Elephants, Lions lying under bush just feet away from the road didn't seem to care about the dozens of vehicles stopping for Photos. Saw a migration of several 1000 buffalo which was also cool. The list goes on and on, I would call it a life time experience. Never run out of things to see.
Do it!!