I ask because the WD Green http://www.newegg.com/Product/Product.aspx?Item=N82E16822136359 and the WD RE2 are pretty similar minus the cache yet the RE2 has a 5 year warranty instead of the Green's 3. Because of this I am thinking of going with the RE2 instead but I won't be using it in RAID if that matters. Is there anything else I am missing?