which one of these cameras you recommend me ?

Hello,

I have narrowed down the choice of a digital camera for general
purpose and for rarely if needed also underwater to these cameras:

I want a camera that will take very good pics also at night, with low
light and mainly when travelling, so also not so heavy and compact in
size if possible.

Rarely I may use it for underwater photography so if case available
better.

Which of the following models you recommend me ?

Olympus C5050 or C6060


Canon: G5,* S50, S60 or A80

Any other brand or models you recommend me ?

I dont even know if the above models are still produced.

Thanks,

Mario