I always used to slept with a top sheet, but soon after Tom and I started dating I discovered that he never did. (In general: Americans do, Brits and Europeans don’t.) Then when we moved in with each other in London, we went without one. It was such a change that at first I wasn’t sure what to make of it, but after a little bit of time I was a total convert. And now I would never even think of sleeping with a top sheet!
It feels like slipping into a hotel bed when all you have is a cozy duvet cover, and I love it. We use these sheets, which are super soft. (The fitted sheet lives unused in the bench at the foot of our bed :))