Wrapsol ultra front and back, plus Apple bumper.
If you are afraid of scuffing up the metal band with the bumper (which it will), apply transparent but thin tape on the band as well (3M tapes are good once you cut em to fit the band). Since its all covered with the bumper anyway, you won't see the tape.
Alternatively, you can also apply the Wrapsol on the band, but the bumper then will fit tight and will stretch out a bit to accommodate it. You don't necessarily need the bumper with the Wrapsol, but its extra level of protection if you drop it. And provides a nice slip-free grip. Has saved my phone from drop damage few times (though the bumper got nicked a bit).