What are the benefits and drawbacks of children sharing a bedroom?

My both kids, 5.5 years old girl and 2.5 years old boy are sharing bedroom for half year already. So far they enjoy each companion very much, especially before bedtime they will play for a while. Their relationship is very close which I wish to see from the benefit of room sharing. The major drawback is whenever one of them wake up, the other will wake up at the same time due to noise/crying.