Many interesting comments and hints; thank you.

Would like to post these questions based on all the prior responses:

1) Has anyone out there used , seen or had experiences with
"yachtsaver"bags?
Manufacturer is out of business but the idea doesn't sound to bad? Any
Comments?

2) How much is the potential sinking of vessel on the mind of you the
owners?
Do you think a reasonable solution would be welcome? I tshould affect
insurance premiums, right?
What's your feel?
May be I am a bit paranoid about hitting submerged log, halfsunk containers
and the like. But even if insurance may cover loss,can anyone guarantee
life(s)?
cheers mike