I used this exclusively to charge my phone (LG G4, 3000mAh battery) for a few days to see the performance of the charger. I used it to charge my phone both without use and with use. The first charge was without use. It charged my phone from 5% battery up to 100% battery over the course of only 1 hour and 18 minutes, surprisingly fast (1.2% per min). The next charge I did was during typical use, bringing it from 14% to 90% in 1 hour and 13 minutes (1.05% per min), not too far off of the charging rate without use. The last charge was mainly while using the phone as a GPS in my car. That brought the phone from 6% up to 94% over the course of 1 hour 57 minutes (0.75% per min) before the charger was finished.
All things said, the charger worked amazingly well, much faster than the previous iteration of the charger and much better than I expected. I used the charging cable that was included with the charger for this test, but have been using my own cables since then as I have much shorter cables that I prefer for some cases and much longer cables for others.