Have to agree with Rich, nothing really to be gained especially on the intake side. I'll usually do the exhaust main and sub ports and dome just to help keep carbon from attaching. If the intake side and transfers get a lot of rework and if it's for a customer I like to clean and blend the rough work out. My own stuff might get left raw. When someones paying good money they expect a decent finish look, or if you know pics of your stuff might end up online you tend to make it a little prettier than need be. I've never seen polishing hurt anything so I wouldn't be afraid of it.