Reviews of OEM Volkswagen cylinder head

The 2.8L 24v head has a bare port flow about what a well ported 12v one does. However, at low and moderate lifts, the 24v will kill it, which is what really matters.

I am really dissapointed with the 2.8 24v head

The AXW head is very decent for bone stock/OEM numbers, especially when you factor how much work and money you put into a 1.8/2.0/ABF head to 'maybe' get close to those flow numbers.

Yes,as long as both heads match each other. The diameter of the valve's heads between a 1500 and 1600SP are ever so slightly different,so leaving an old 1500 head on one side of the engine and putting a new 1600SP head on the other side might change the intake flow characteristics,making 1/2 the engine work easier or harder than the other,kinda unbalancing the engine as a whole which could put more stress on the internals shortening it's overall life,like someone walking with a limp messes up their spine over time. It's always best to replace just one with an exact match to the other or upgrade both at the same time .

I see you have a Digi Head there, when I took mine off, (with over 130K) it didn't look that bad!, and it was headed to the machine shop to have new valves put in after I bent one, and blew the gasket