I remember the first time I wore a one piece after the age of five. I was shopping with my best friend my sophomore year at the University of Miami. She pulled out a one piece, looked at me and said, "Please try this on." Now this was shortly before the one piece trend took off so my reaction was, "No thanks. Try again." But she prevailed, bullying me into trying it on and buying it, thus sparking my love of the one piece. They don't fall down. Big plus. You can sit/lay/lounge any way you want. They look good. And, bottom line, they are INCREDIBLY comfortable.
The one piece is timeless, and I've found a few brands that never let me down.
Wearing: Dolce Vita one piece