Performance Coatings gives good results, and they are local to me so that's convenient. I've used their heat-blocking coatings on a turbo hot-side housing, downpipe, etc. on my turbo Miata, and their shiny-finish stuff looks pretty nice on valve covers etc. too. Not cheap though!
So we have one vote in favor of VHT paints and a few negative experiences with paint on exhaust manifolds. I am eventually going to be looking for a "cast iron" look finish for my ram-horn manifolds. I've just finished using some cast-iron-appearing paint my transmission parts, and it looks awesome. For exhaust manifolds, though, is it worth the considerable extra expense to go to a ceramic coating as opposed to VHT paint? (I am not afraid of doing multiple-step surface prep, unlike many hobbyists; the local autobody supply guy sells me a whole lot of cans of pre-cleaner and etch primer.)
