We always have two offerings on nitro, our IPA and a honey porter, but with stouts, nitro just works. I think that stouts are actually less enjoyable carbonated because of the carbonic bite. It leaves a little bit of that acrid bitterness from the roasted malt. In really big, viscous imperial stouts, a high level of carbonation can be harsh. But nitro smooths out the stout, softens its edges, and enhances the mouthfeel. It adds more to the body, leaving you with an enjoyable drinking experience.
Last year, we did a "white stout" called Ties the Room Together for Left Hand Brewing’s annual Nitro Fest. It was basically an imperial cream ale, and all the ingredients worked well together. It had a nice, heavy body with cocoa nibs, coffee, and vanilla. It was on nitro, and all those deep flavors just came through strongly, in a harmonious way, and I think part of that was because of the creamy nature of the nitro.
Nitro beers are smoother because the solution is about 30 percent carbon dioxide and 70 percent nitrogen. The latter is mostly insoluble in liquid and is the readon why the beer has that creamy mouthfeel. When beers are poured properly through a restrictor plate on the nitro tap, you get that great pour and a firm head on top of the beer.