Well, it's up to you, but the only way to remove all traces is a full disk wipe. Consider all the stuff that the browser bundle leaves behind on Windows: http://dkn255hz262ypmii.onion/index.php?topic=148291.msg1152452#msg1152452 Consider the difficulties of securely erasing data on a hard drive: http://dkn255hz262ypmii.onion/index.php?topic=99520.msg699299#msg699299 Individual file erasure is not enough. If you really want to get rid of all traces, you need to download DBAN (http://dban.org) and nuke your hard drive, then reinstall the OS. Should you do it with fewer than 10 purchases? Probably not worth it, honestly, but that's up to you.