Have any of you used/heard of doublemyspeed.com or Cyber Defender? I saw it advertised. and I had an old comp so I was like "what the heck" and it seems to have found "840 errors" and I looked through the errors and they seem legit, but i'm still a little skepticle. So should I up the 15$ for this. Or has some one else out there tried it and has an opinion?