Nero,
Your voice will stay low, but not as low if you go off. Body hair will not stay as heavy if you go off, especially not beard growth. It will be sparse if you go off. Now, if you don't get a hysto, then your period will return. Your body will go back to producing estogen as it did prior to being on T. So if you want to maintain the manlyness, then you must stay on it the rest of your life.
Marco