As a baker, I was very happy and pleased with the wide selection of pastry/baking stuff (who doesn't want Silpats, metal cutters, flexipan molds and every size and shape of ice cream scoops) and the gamut of kitchen necessities that you would want in your kitchen cabinet. As these gadgets are precision tools, I must warn you that prices are rather steep, but remember they're long-term investments.
Also, it's worth pointing out that JB Prince is not visibly located along the street. The store is located inside a nondescirpt Midtown office building, on the 11th floor and behold JB Prince. Even if you don't have any intentions of buying something, you'll find yourself carrying a loot bag!