Probably a lot easier to get at the age of 21 than a vasectomy has proven to be.
Well, aside from the fact that it hasn't exactly been released to the public yet at all. The age of 22 or 23 then, perhaps.
And it doesn't involve messing around with hormones like the women's Norplant does, either. It's always only women whose hormones have to get messed around with. If I wanted my hormones messed with I might be an FTM by now. I don't want my hormones messed with. It sounds creepy.