Hi, I want to get seamless wifi coverage throughout my apartment. Its about 3000 square feet and rectangular in shape with the cable modem at the center of the apartment (I don't get signal at rooms towards the ends). I currently use a 300 mbps dlink router. Can airport express solve my problem? Would I need multiple devices and would they act as repeaters (thereby lowering my speed)? I'm fed up with flaky wifi around the apartment. Thx!