I'm not knocking any of the chargers mentioned ..
IMO, if your paying near or over $200 for a new charger, it better have dual ports, and each of those ports should be capable of charging at the max.
The GFX is the only exception to this becasue it can straight up discharge at 35A, without any tricks (external battery, etc.)
I've seen some dual chargers capable of 20A on one side and like 6A on the other, not a fan of that.