Wow! These two cameras have very few similarities.

The SD300 is an ultra thin point-and-shoot camera.

The V1 is an advanced camera with all of the necessary manual controls and features.

Picture quality is about equal, but the V1 shows more detail (more megapixels).

It depends upon what you want in a camera.

If you want a camera and don't need or want to get involved with the mechanics of photography, get the SD300.

If you are interested in photography and want to get more deeply involved with improving your photos, get the V1.

Here is a side-by-side view of the specifications:

http://www.dpreview.com/reviews/compare_post.asp?method=sidebyside&cameras=canon_sd300%2Csony_dscv1&show=all

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