This add-on does exactly as it is described to do. All of my new users immediately have their avatars changed to their proper Minecraft skin head, and it adds a little bit more flair to the site.
The only reason this add-on doesn't get five stars from me is because it lacks the ability to add avatars for members who have already registered and never added a profile picture. The best addition to this add-on would be to make already registered users WITHOUT a profile picture use their Minecraft skin head as well.
Other than that, this add-on is fantastic and I would recommend it for any other Minecraft server owners!