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The prospect of having to pay for future logten updates doesn't sit well with me. A logbook is something that a pilot takes with them their entire career, and the costs of inevitable updates will no doubt add up.
FWIW mccPilotLog has a one off cost, syncs across mobile devices (apple, android, windows mobile) without having to pay extra for the mobile versions, and has more or less the same features. Logten pro has better visual appeal, but other than that it just seems horribly overpriced for what it is.