Exhaust Gasket from header to ex.pipe

[Long Knight]

I am going to replace the paper gasket between my header and exhaust pipe coupler (triangle shape with three bolt holes). I am wondering if you have to use a flat gasket or if you can use a doughnut gasket like they use on ram horns? Those doughnut gaskets seem like they work good.

I got a set of these thin copper flat gaskets I am thinking about trying to seal the suckers up. Are those good to use? If not I'll take them back because they were a little pricey. I'm just tired of hearing and smelling the exhaust leak!

Thanks everyone!