My guess is that the OP means knowing where you download from. In a way it's like the fabled "web of trust". Reputable warez groups didn't distribute software with viruses.

Like the OP, back in the day I used to have plenty of pirated software (mostly games) and never had a problem with viruses (at least, not that I knew or had any noticeable effects). The threat complexity is probably way worse these days and I wouldn't risk it. Plus, of course, I support games by paying for them :)