Advantages of the ES over SPY ?

[comintel]

Quote from Wide Tailz:

ES and SPY back test differently for the same strat. The result$ are quite different.

:eek:

Their quotes are almost identical (apart from factor of 10, differing hours and leverage, and slight differences due to cash versus futures). Of course they are arbitraged against each other by many bots so they are all but identical apart from those minor adjustments.

 

[JohnHar]

as for me I would choose S&P as the instrument requirs less margin (leverage). other the same..