Data recovery professionals will tell you that SpinRite is a drive killer. This is because it hammers away at bad sectors up to several thousand times hoping for just one good read. This approach can dramatically accelerate the failure of a bad head. Even if it is successful, it then writes the data back to the same drive rather than to a clone.
The best approach is to clone your drive, sector by sector, using a utility (eg ddrescue) that understands how to work around bad media. Then use data recovery software on the clone.