AF-S VR Zoom-NIKKOR 70-300mm f/4.5-5.6G IF-ED (4.3x) Vrs AF-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR

what is the difference between AF-S VR Zoom-NIKKOR 70-300mm f/4.5-5.6G IF-ED (4.3x) and AF-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR lens. I am planning to buy a 300mm lens, whats the major difference between these two lenses apart from shortest focal length(55, 70) as there's difference of almost 50% in both of these cost. Please Suggest.