expensive recovery services go much deep than the software solution. So the rule of thumb is this: If it's some data that you'd like to recover but isn't considered critical (music, videos, etc), the software solution might be okay. But if it's mission critical stuff (like vital files for work) that will pontentially cost you or your company thousands, you really need to look at the recovery service. In fact, by using the software solution you may be putting the data in more jeopardy by continuing to run the hard drive, especially if it has hardware damage. In those case, you should unplug the HD immediately and look into the recovery service. They would normally remove the platters from the HD and try to read from them in "clean room" environment. This is the safest (though still not guaranteed)way to recover data. Yes, it's expensive, but if the data is worth more than the cost of the service, you don't want to leave it up to a software solution that may further damage the HD.
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