I always find it hard to trust free. Even with T&Cs/ToS/Privacy, if I'm not paying for it, I feel that its all lies. Combine that with a site that looks like that, and I'm assuming my PDF will have a virus attached to it.
Sure, but you're thinking about that kind of stuff even slightly, you're not going to be uploading your documents anywhere. I suspect the Venn diagram overlap between "thinks about online security" and "uploads documents to random web sites, even if they cost money" is small.
If it's anything I need to care about privacy with, I'm not uploading it to someone else's server even if I pay for it, I'm doing it locally.
But if it's say, as a friend recently experienced, a handout from a teacher in Corel Draw format, you bet your ass I'm uploading it to whatever the top google result for "convert corel draw to pdf online" is.
