Tether is a huge scam. There was an interesting article on Medium that spoke about all the pitfalls of tether and how Bitfinex is simply using it as a means to cover up their inability to provide fiat holdings.

If you need to move into fiat, don't choose tether, because despite it saying "USDT" it's not the same as USD! Tether is an altcoin, same as litecoin, except that it tries to stay close to the USD price. They have different tethers for different currencies... but all of them are scams.

If you want to convert your crypto to fiat, just send them to gdax instead and sell it FOR REAL fiat. That's the safest way.