The Harbor Frieght can do almost 20A on my bank but you need something to reign in the voltage like one of those VARIAC's. That was with the old Paramode converter doing the initial charging which I now think wasn't getting the SOC very high. The VEC and IOTA get them much higher so the amps on the HF charger don't get much over 10A (typically ~8A). That's with the 10A setting. The 2A setting does 2-4A.
EDIT: I wonder if that new HF charger works like the old one did. Someone's gonna have to guinea pig the new one for us. :)