Gasket cement on header/intake gasget.

Do you guys recomend copper coat or any kind of gasket sealer on an exhuast manifold gasket? I have a Fel-pro gasket and the one that came with an APN header. Any problems with just picking the nicest looking one and bolting it on as is?

No waste of time and money. As a rule never use any kind of sealer on a gasket.
I have pulled and replaced more then a few intakes and never doped the gasket.

I'll use a thin layer of RTV Copper on the manifold gasket.

Reason? Inline sixes tend to have the screws work loose over time (I check mine annually, and usually find one or two loose,) especially with an aluminum intake and an iron exhaust and common screws. The RTV helps keep the gasket sealed and helps to prevent "burn-through" when the screws do work loose. It's not required, but I've found it helpful.

Just finished doing this about 20 min ago (engine out of jeep) , and follow the torque sequence and specs.