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Full user review
"Good but limited functionality"
Sometimes fails to capture a selection when doing several "snaps" in a row. Always works the first time opened (version 2.5.7 with OS 10.6.4) but then seems to be an issue with subsequent actions. Closing and re-opening the app solves the problem.
Because of the "Con" above, I highly recommend the free and much more capable Skitch.