Happily, I have no experience at ditching 310's (or anything else!). I do, however, have a hundred hours flying the same model 310 shown, and can attest to it's having one of the best fuel systems, and fuel quantity indicators I have ever flown. The one I used to fly also had wing locker tanks. If I remember correctly, those six tanks would get you about 1300 miles, so that plane would have to have been tanked for such a long flight.
I compare the C 310 fuel system, to that of the C 303, which I copiloted Transatlantic. The 303 fuel system, though much more simple, and error resistant, was nowhere near as nice, or reassuring for a very long flight.
Nice job ditching!