For me it doesn't feel much like reality at all. The only part that feels totally real and awake is my mind and my ability to think. The least real part is probably my observation of my physical surroundings in the dream. Even though I'm totally aware of where I am and what I'm doing, I still always have the same difficulty to open my eyes and look around. Maybe that's partly because my mind just isn't capable of constructing a complex surrounding out of nowhere.