I remember the quote from my cfi on the air squadron, a very experienced hunter pilot telling us in line with Sharpend has said, 'there are old pilots and there are bold pilots. There are no old, bold pilots'
As for planning to fly over large bodies of water with a fixed undercarriage sep, he said the very 1st thing is to do make sure your affairs are in order.
I know engine failures are vrare but i see people taking family or friends to alderney or scilly in a PA28 etc. and to me thats madness. High probabily of the plane flipping over and i'd bet my house the child/adult in the rear left had seat is not getting out alive, if any one does.
And for me its the 3-4 minutes after its all gone quiet up front knowing that you are probably about to kill everyone on board.
But each to their own as long as they (and their family) are aware of the risks.