Those look great!
I had looked at underwater disposables closely for typical beach summer snaps. It appeals my inner LoFi toy camera persona and the kid inside. It evokes warm childhood memories of the beach, film snaps et al.
I don't recall using disposables in the family as a child however.
I did shoot a bit with my cellphone on the beach and the snaps were great, however, no way it is getting any closer to the sand and water. If it were one of these waterproof models that have appeared this last year I'd had paid a second thought.
Anyways it's a great option for that occasional sea shooting. Bettered perhaps by some thrift underwater P&S.