Despite its name, Rou Gui or Cassia tea doesn't resemble cinnamon very much. It does have a bit of spiciness to it, like most WuYi oolong teas, but cinnamon is not there. It also has a bit of floral notes, which is also expected. Some people say, it reminds them of dried strawberries.
There are many oolongs from WuYi mountains. They all share some characteristics, but they all have a different feel to it. This one has a strong feel. It's not as delicate as Shui Xian, but it is also not as direct and rough, like Tie Luo Han. For me, this one is the most similar to Da Hong Pao, but since it is not as common and demand is not as high, Rou Gui usually has better quality in the same price bracket.