A620 v. S70 (picture quality)
The images at the middle are the same, but the A620 is better at
the edges and way sharper at the long end of the Zoom and there is
less Purple fringing - I always class the S70 as a camera with a
28mm Prime on which happens to zoom in an emergency..
My experience with the Canon S70 is quite different - and I've put over 9,174 shots through mine since June/7/2005 (please see the links in my sig. the 2005 page has 116 albums averaging over 30 shots/album....)
Here's a rather good example - from an outdoor concert where I was not at the front of the stge - and even the zoom at 100mm was really inadequate - or so I thought.....
Crop from edge of frame-
which came from the full frame -
Now even I'm impressed!
Please see this thread on the S70 with lots of examples and test shots -
Specifically on edge and corner definition -