The upside of Tremont's gentrification is that it's provided a rare oasis of affluence to the West Side. The downside is that it's become a bit too fancy for anyone with paint stains on his Dickies. The Prosperity Social Club straddles this divide. For regular types, it's an upscale neighborhood bar without the pretense and prices. To the more sophisticated, it offers a classy 1938 feel, with a kitchen serving everything from hummus plates to stuffed grape leaves. In short, it's the one place that seems to understand West Side old and new -- a joint that aspires to more than Tic Tac Fruit and Jäger bombs, but knows you don't have to get all sphincter about it.