Apple's refurb store has the late-2013 2.6ghz 15" Retina MBP and the mid-2014 2.5ghz 15" Retina MBP on sale for the exact same price. The specs are otherwise identical other than the 0.1ghz clockspeed difference. Is there any reason NOT to buy the Late 2013 model with the faster processor? Are these two models really the same other than the clockspeed?