I would argue that this is the best program out there for hard drive recovery. NOt free though. But you can also use it for maitenance to keep your drives in optimal condition. It will recover all drives regardless of OS or partition format. You can use it on PC, Linux, Tive, Mac, Apple TV. It reads the drive at its lowest level, repairs and marks bad sectors.
GRC*|*Hard drive data recovery software**

I'm not alone, read some of the customer feedback also.
GRC*|*SpinRite 6.0 Experiences and Testimonials**