Counter tops from Chinese Vendors in Flushing?

Does anyone have experience with one of the those kitchen cabinet/countertop vendors in Flushing along College Point Blvd? I checked a few over the weekend and saw that their prices are relatively low compared to home depot/Loews or even Ikea. They have granite starting at $35/feet and Quartz at $25/feet. Installation is separate, which cost between $200-$300 or $10-$15 more per feet for a 25 feet countertop.