I've never heard of 10,000,000:1 and besides that spec, there doesn't appear to be much difference in the three.
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236100
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236052
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236100
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236100
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236052
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236100