I take raw files from my 7D and enlarge them to 49.9MB using CS2 ACR conversion, which offers this size directly (no need to open in Photoshop then uprez). This size is required by Alamy.com, the agency I sell pictures through - only about one a week, $600 to $1000 a month income, but well worth it from the travel and incidental shots I take in the course of running photo magazines.

The 7D image is focused more on the face, and the Alpha shot on the hand, and they use different lenses - 7D, the 24-105mm at 105mm and f5.6; A100, the 100mm prime at f4.5. Some idea of relative detail, noise size, noise obtrusion, chromatic fringes, purple highlight 'blooming', sharpness and other aspects can be gathered by this comparison where both source images have been taken to the same 5120 pixel height, then identically cropped. This is a fairly effective way of seeing two different sized digital images in the same light - their true detail level, not a 100 per cent view of two different size files.