Yup! I did get the double size mattress, but I'm alone so it works for me. Might be too tight for a couple. It only gives you 3" of space on each side, but that's just enough to get your hands down.
Before that, though, I bought a long handled, plastic flat spatula to push the fitted bottom sheet down over the corners and it worked like a charm. Might take a bit of practice, Karen, but it beats scraping your knuckles every time. My bed is up against walls on 3 sides, so putting sheets down over the mattress while kneeling on it is a real challenge!
Evie