As with the 7.2-megapixel PowerShot SD550 Digital Elph, our current Editors' Choice in the high-end ultracompact category, there's a lot to like about the 5MP PowerShot SD450 Digital Elph ($399.95 list). In fact, both have many of the same features. Yet there comes a point when a camera is a tad too tiny, and the SD450 may have reached it. For those with larger hands, the buttons and dials may be too little to use comfortably.