We bought both the Nara Park Classic Tour and also the Afternoon Old Town Stroll.
We really enjoyed the tour. It started in the Nara JR station and we rode the bus which was included in the tour, so we didn't have to care about the fare. The tour was informative and our guide Yachiyo was very kind and told us a lot about Nara history, the temples, differences between shinto and buddhist shrines, showed us how to pray there....sometimes there was a bit of struggle with English, but we always managed. In the end we were a group of 7 people and we enjoyed the walk in such small group. In the end she showed us the streets with lots of restaurants so we didn't have to search long for a lunch.
We (2 people) were the only visitors for the afternoon walk, so we had an (pleasantly) unexpected private tour. We walked the old town and learned a lot about the Edo period, local history, religion, we learned a lot, for example the role of konyak, shogi-san and substitute monkeys in the local folklore. We already had a bit of a knowledge of Japan history and this was great addition and miss Yachiyo seemed very pleased by it. In general we really enjoyed the whole day we have spent with Yachiyo.