I'd add parachutes for everyone as a safety feature - bailing has got to be better than ditching.
If you ditch in a fixed undercarriage, is the plane going stay up right?
No.
When you are upside down, having been thrown about a fair bit and sinking are you going to be able get out?
Maybe.
Are your passengers in the back?
No.
Its not madness to do 200nm over water in a single, but you and any passengers must be aware the chances of survival in the event of donk stop are pretty slim.