Thought I'd share a weekend story; hopefully I'm not violating any standards of the site by mentioning a product. I've enjoyed serious sailing for the last seven years; many overnights, including one and two-week trips each year. Nothing like hitting the sack at 10 and waking at 4 with a sore back, but a great chance to see the sun rise. We have the standard 3" foam mattress I'm sure is found in most boats. Waking at 4 isn't exactly my choice, but the bed is barely comfortable and I never sleep past 6 any morning, boat or not. Bought and installed the Froli sleep system. Basically a spring mattress that can be accommodated to any space, such as our front V-berth. Here's my new problem - slept in til 8:43. Couldn't believe it. Don't know whether to complain that I'm missing the sunrises, or appreciate the better sleep on a vastly improved bed. If you're an early riser, don't get a Froli. For the rest, give it a thought. I'll let you know what my wife thinks when she wakes up. Paul