PSA: NEVER Return a Free Device to Metro! You won't get your money back!
Tl:Dr: If you return a free device that you had to buy a line for, you will get a $0 refund to your card, and the cost of the line will be credited to your account. This is of course WORTHLESS if you don't intend to pay for the next month of service on that account anyway.
I was sent a defective Tab A9 tablet, with a damaged screen. Following customer service advice, I sent it back to MetroPCS. The received and processed the return, refunding me absolutely nothing. They then credited $20 to my next billing cycle, which I don't intend to pay.
So now, I have no tablet and no money.
If you get a defective unit, contact the manufacturer for warranty claims, you will get NOTHING from Metro.