I had this one. Costco had a pack with a variety of USB chargers. They buzzed loud enough to bug me so I brought them back.
I tried a USB receptacle, but in the most convenient location in my house, I have the four wires (2 circuits on one double breaker) so it wouldn't go into that box.
I just use the chargers that came with my phone and seem to get by ok. At some point I'm sure I'll try one of the built in receptacles again.