Quote from Painkiller:
I heard order size is also a big factor in getting fills. Maybe less pertinant for the SPX but as it relates to other futures options I believe it's important. Could you confirm this? Do you have an easier time getting fills for, say, 10 contracts than you would for 1 or 2?
When considering SPY options in particular, I have found that lots of 10 seem to get better fills than individual contract orders.
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