Aqu small port ko3s think 19mm wrist pins has vvt and map sensor,sap,and crappy clips on rear charge pipe.
agu big port ko3 20mm , none of that crap.and alot better charge pipe.
I think aqu/aum are easier/better to map
I am running a ko3s agu. Daily
And an aqu with agu wrist pins/con rods and aftermarket bolts,agu rear charge pipe.
I think the different between aum and aqu is the ecu and some breather pipes, but unsure as it's only what I read.
Hope that helps
Oh and the aqu runs a n75f valve as standard(or e if it's been updated)