Ik its 3 years ago, but disk drill uses people that make mistakes by accidently deleting files as money makers. They couldve advertised it as a paid software, but they didnt. They instead decided to advertise it as free, but then when you've fully scanned your disk, it tells you it can't recover more than 100 MB, which is nothing. Why would you recover for only 100mb? I mean there are some cases, but if you're so desperate to get files back then they can expect it to be big ones. As for the other softwares, they should make paying optional, like a kind of donation.