I have the MAF 6-1 headers, never had the truck without a header so I have nothing to compare it to. I have no vapor lock, no issues starting/warming up with a little choke and gas pedal pump. It's a great place to add chrome!
I do have a heat riser installed and I am fully desmogged.
I just put on a new one. Copper gasket sealer and a felpro gasket, sealed it up nicely.