Everything, to my knowledge on this site is free. Kevin has made some amazing music, and you can even get free graph paper!
There's nothing on this site that isn't inappropriate, except for the horror background music that you can find that is painful to the ears, but other then that, it's a really nice site.
Personally, I usually don't download from anywhere except for credible companies. So even though it's probably risk free, I don't think that I'll take that small possibility of retrieving some kind of virus. But that's just me.
This website is a treasure trove of brilliant royalty free tracks. Its quite literally music to the ears of desperate YouTube video creators trying to find tunes they can legally add to their monetized videos!
It always has what I need. You won't find a better free & royalty free music website. Its easy and safe for everyone!