I have a brand new AE86 HKS Super Header II 4-2-1 stainless manifold.
It is the best manifold for the 4AG I have seen from Japan, has superb welding, open-ended gussetting and the tubes are firmly located inside the baseplate before welding for utmost strength and durability. This thing is a million miles from a Janspeed!! And 4-2-1 is nicest for a bit of useable mid range, not all up top.
Wouldn't sell for less than £450 though... it really is the dogs bollocks.