I could not find enough information on the Samsung to have an opinion.

The A400 is Canon's entry level point-n-shoot camera.
Produces good photos.
Will close focus (macro) to 5 cm. (about 2 inches)

The CX7330 picture quality is below the A400.
Will close focus to only 15cm. (about 6 inches)

The A75 is a step above a point-n-shoot and has all of the major manual over-ride controls. In Auto mode, it will function as a point-n-shoot.
Picture quality is better than A400.
Will close focus to 5 cm. (about 2 inches)


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