Isn't that in itself a bit risky? A program that will need to send stuff from your computer to the company that produces it?
You need to trust that company completely, make sure they won't be sending your cacheed bank passwords and card numbers.
Yes it is risky.
The Hitman Pro folks have a good reputation, but yes, in the end that is all you have. They do upload only executables, or so they say.
Yes, you need to trust them. But no, "trust completely" is probably overstating it. Many folks are blissfully unaware of just how risky their computing is already.
As I alluded to, Hitman Pro can cure some really really nasties when nothing else will, but it is not a cure of first resort.
To everyone, you will know you have big problems when clicking on a Google search result frequently takes you to unexpected spam.