As a professional photographer working with conventional silver halide images, I was surprised and impressed by the functionality and simplicity of these digital cameras.
Optically, all these cameras perform to a similar standard.
Only handling and feel is different in all cases.
My recommendations are based on ease of use and the feel of the camera in my hand. For all the cameras, I would purchase larger memory cards than the ones supplied, an 8Mb card fills up very quickly (approximately eight images).
But a word of advice.
These cameras are all designed for amateur use.
They will not turn the amateur snapper into a professional photographer. They will produce exceptional results in poor lighting conditions.