Rosa Mexicana, the upscale eatery begot in NYC, will be opening a location at Seaport West on the South Boston waterfront. The Boston branch will be the 13th restaurant of its kind with others in Miami, LA, and... Hackensack! The company's website invites you to "indulge your sense in an oasis of bold Mexican flavors" but on Chowhound resident Boston food guru MC Slim JB is wary. He writes: "I'm not dismissing Rosa Mexicano out of hand -- I welcome good new restaurants of any stripe -- but I have frequently questioned the market's ability to support the flood of new Yanqui Mex places that opened this year. One of them already came and went, Jalapeno's in Allston."