I bought the Anker PowerPort II and so far it works great as a basic charger, however, I have noticed a few issues with it.
I've tried charging my 2017 MacBook pro with this plug and a usb c to usb c as well as a usb a to usb c and it only seems to maintain the charge rather than giving it any juice. I used the apple brand usb c to usb c and a third party (not anker) usb a to usb c.
I've also noticed when charging my Iphone 8+ with a third party usb a to lightning meter long cord, the charge isnt exactly fast. When I use an apple brand usb a to lightning cord I don't seem to have this issue.