I don't think KerryGold has an after-taste. It tastes richer, with a higher fat content, than Land O Lakes.
One butter that has a "tang" to it which I like even more, is the Trader Joe's "Cultured" butter made in Brittany.

Regular US grocers are getting butters with higher fat content now, called "European" grass-fed milk butters, brands like Finlandia. seen that in Walmart, Sam's, local grocers. KerryGold is in Costco in four packs.