I have been using futures but have noticed the tight penny spreads on the SPY. Tax treatment favors the options on ES but that spread on the spy is attractive especially when dealing with the large spread on OTM futures options. Anyone done any work on this they would be generous enough to share?
Even if you're in the highest tax bracket, it makes more sense to trade SPYs. You do run the additional risk of early exercise though...American as opposed to European options and so forth.