The dickhead is called the glans/head. Saying dickhead like that might confuse people that are you calling them a name. :D
You can’t get any more from those devices then what you can with your own hands. 3 inch in 60 days is bullshit, but I suspect you already knew that. Once you have exhausted your newbie gains, you need to step it up a bit. And hanging or an ADS (All Day Stretch) device is a way to do that and can get gains from your newly conditioned penis. Lots of guys have gained here from them. But it’s not some huge amount and it takes time and patience like anything else. It’s not more then what they would gain if they just manual stretched (as far as I have read, but different people have said different opinions on that). I haven’t hung or used ADS, I’m just going on what I have read from people here. But it’s said something like x number of hours or something before your penis will start growing from it? X being a very high number of hours. Hopefully some of those guys can post here and share there experience.
There are progress threads from people who have used these devices. I suggest you go have a look at the progress thread forum, or do some searching and read up on it.